diff --git a/20231207/bogosort-1.c b/20231207/bogosort-1.c
new file mode 100644
index 0000000000000000000000000000000000000000..6f8f4fe71606cb33ae7b1382cb5361a4f49c9e04
--- /dev/null
+++ b/20231207/bogosort-1.c
@@ -0,0 +1,66 @@
+#include <stdio.h>
+#include <stdlib.h>
+#include <string.h>
+#include <unistd.h>
+
+int comparisons = 0;
+
+void display (char **name, int left, int right)
+{
+ printf ("\e[H\e[J");
+ for (int i = 0; name[i]; i++)
+ {
+ printf ("%s", name[i]);
+ if (i == left || i == right)
+ printf (" <--");
+ printf ("\n");
+ }
+ printf ("%d\n", comparisons);
+}
+
+int compare (char **name, int left, int right)
+{
+ int result = strcmp (name[left], name[right]);
+ comparisons++;
+ display (name, left, right);
+ usleep (200000);
+ return result;
+}
+
+int is_sorted (char **name)
+{
+ for (int i = 1; name[i]; i++)
+ if (compare (name, i - 1, i) > 0)
+ return 0;
+ return 1;
+}
+
+void mix (char **name)
+{
+ int n = 0;
+ while (name[n])
+ n++;
+ for (int i = 0; i < n; i++)
+ {
+ int j = rand () % (n - i);
+ char *temp = name[i];
+ name[i] = name[j];
+ name[j] = temp;
+ }
+}
+
+void sort (char **name)
+{
+ while (!is_sorted (name))
+ mix (name);
+}
+
+int main (void)
+{
+ char *name[] = { "Otto", "Lisa", "Anna", "Heinrich", "Siegfried", "Peter",
+ "Dieter", "Hugo", "Berta", "Maria", "Fritz", "Box", "Hans",
+ "Thomas", "Ulrich", "Zacharias", NULL };
+ sort (name);
+ display (name, -1, -1);
+ return 0;
+}
diff --git a/20231207/bogosort-2.c b/20231207/bogosort-2.c
new file mode 100644
index 0000000000000000000000000000000000000000..3120ed170739dee09fe3182637c0b2369efc006d
--- /dev/null
+++ b/20231207/bogosort-2.c
@@ -0,0 +1,64 @@
+#include <stdio.h>
+#include <stdlib.h>
+#include <string.h>
+#include <unistd.h>
+
+int comparisons = 0;
+
+void display (char **name, int left, int right)
+{
+ printf ("\e[H\e[J");
+ for (int i = 0; name[i]; i++)
+ {
+ printf ("%s", name[i]);
+ if (i == left || i == right)
+ printf (" <--");
+ printf ("\n");
+ }
+ printf ("%d\n", comparisons);
+}
+
+int compare (char **name, int left, int right)
+{
+ int result = strcmp (name[left], name[right]);
+ comparisons++;
+ display (name, left, right);
+ usleep (200000);
+ return result;
+}
+
+int is_sorted (char **name)
+{
+ for (int i = 1; name[i]; i++)
+ if (compare (name, i - 1, i) > 0)
+ return 0;
+ return 1;
+}
+
+void mix (char **name)
+{
+ int n = 0;
+ while (name[n])
+ n++;
+ for (int i = 0; i < n; i++)
+ {
+ int j = rand () % (n - i);
+ char *temp = name[i];
+ name[i] = name[j];
+ name[j] = temp;
+ }
+}
+
+void sort (char **name)
+{
+ while (!is_sorted (name))
+ mix (name);
+}
+
+int main (void)
+{
+ char *name[] = { "Otto", "Lisa", "Anna", "Heinrich", "Siegfried", NULL };
+ sort (name);
+ display (name, -1, -1);
+ return 0;
+}
diff --git a/20231207/bsort-1.c b/20231207/bsort-1.c
new file mode 100644
index 0000000000000000000000000000000000000000..3c02adc72e6a7e702e2c7c68c838fc94cc8ef547
--- /dev/null
+++ b/20231207/bsort-1.c
@@ -0,0 +1,48 @@
+#include <stdio.h>
+#include <string.h>
+#include <unistd.h>
+
+int comparisons = 0;
+
+void display (char **name, int left, int right)
+{
+ printf ("\e[H\e[J");
+ for (int i = 0; name[i]; i++)
+ {
+ printf ("%s", name[i]);
+ if (i == left || i == right)
+ printf (" <--");
+ printf ("\n");
+ }
+ printf ("%d\n", comparisons);
+}
+
+int compare (char **name, int left, int right)
+{
+ int result = strcmp (name[left], name[right]);
+ comparisons++;
+ display (name, left, right);
+ usleep (200000);
+ return result;
+}
+
+void sort (char **name)
+{
+ for (int i = 1; name[i]; i++)
+ if (compare (name, i - 1, i) > 0)
+ {
+ char *temp = name[i - 1];
+ name[i - 1] = name[i];
+ name[i] = temp;
+ }
+}
+
+int main (void)
+{
+ char *name[] = { "Otto", "Lisa", "Anna", "Heinrich", "Siegfried", "Peter",
+ "Dieter", "Hugo", "Berta", "Maria", "Fritz", "Box", "Hans",
+ "Thomas", "Ulrich", "Zacharias", NULL };
+ sort (name);
+ display (name, -1, -1);
+ return 0;
+}
diff --git a/20231207/bsort-2.c b/20231207/bsort-2.c
new file mode 100644
index 0000000000000000000000000000000000000000..d277be0182a40ecd0c66eaeef94d7aebac6aa542
--- /dev/null
+++ b/20231207/bsort-2.c
@@ -0,0 +1,55 @@
+#include <stdio.h>
+#include <string.h>
+#include <unistd.h>
+
+int comparisons = 0;
+
+void display (char **name, int left, int right)
+{
+ printf ("\e[H\e[J");
+ for (int i = 0; name[i]; i++)
+ {
+ printf ("%s", name[i]);
+ if (i == left || i == right)
+ printf (" <--");
+ printf ("\n");
+ }
+ printf ("%d\n", comparisons);
+}
+
+int compare (char **name, int left, int right)
+{
+ int result = strcmp (name[left], name[right]);
+ comparisons++;
+ display (name, left, right);
+ usleep (200000);
+ return result;
+}
+
+void sort (char **name)
+{
+ int sorted = 0;
+ while (name[sorted])
+ sorted++;
+ while (sorted > 0)
+ {
+ for (int i = 1; i < sorted; i++)
+ if (compare (name, i - 1, i) > 0)
+ {
+ char *temp = name[i - 1];
+ name[i - 1] = name[i];
+ name[i] = temp;
+ }
+ sorted--;
+ }
+}
+
+int main (void)
+{
+ char *name[] = { "Otto", "Lisa", "Anna", "Heinrich", "Siegfried", "Peter",
+ "Dieter", "Hugo", "Berta", "Maria", "Fritz", "Box", "Hans",
+ "Thomas", "Ulrich", "Zacharias", NULL };
+ sort (name);
+ display (name, -1, -1);
+ return 0;
+}
diff --git a/20231207/bsort-3.c b/20231207/bsort-3.c
new file mode 100644
index 0000000000000000000000000000000000000000..67d0097b913171b4523f4f04b6b6ff494046dabd
--- /dev/null
+++ b/20231207/bsort-3.c
@@ -0,0 +1,58 @@
+#include <stdio.h>
+#include <string.h>
+#include <unistd.h>
+
+int comparisons = 0;
+
+void display (char **name, int left, int right)
+{
+ printf ("\e[H\e[J");
+ for (int i = 0; name[i]; i++)
+ {
+ printf ("%s", name[i]);
+ if (i == left || i == right)
+ printf (" <--");
+ printf ("\n");
+ }
+ printf ("%d\n", comparisons);
+}
+
+int compare (char **name, int left, int right)
+{
+ int result = strcmp (name[left], name[right]);
+ comparisons++;
+ display (name, left, right);
+ usleep (200000);
+ return result;
+}
+
+void sort (char **name)
+{
+ int done = 0;
+ int sorted = 0;
+ while (name[sorted])
+ sorted++;
+ while (sorted > 0 && !done)
+ {
+ done = 1;
+ for (int i = 1; i < sorted; i++)
+ if (compare (name, i - 1, i) > 0)
+ {
+ done = 0;
+ char *temp = name[i - 1];
+ name[i - 1] = name[i];
+ name[i] = temp;
+ }
+ sorted--;
+ }
+}
+
+int main (void)
+{
+ char *name[] = { "Otto", "Lisa", "Anna", "Heinrich", "Siegfried", "Peter",
+ "Dieter", "Hugo", "Berta", "Maria", "Fritz", "Box", "Hans",
+ "Thomas", "Ulrich", "Zacharias", NULL };
+ sort (name);
+ display (name, -1, -1);
+ return 0;
+}
diff --git a/20231207/bsort-3a.c b/20231207/bsort-3a.c
new file mode 100644
index 0000000000000000000000000000000000000000..c475276ae2e17a78afa598f0501ea116aa87ad0f
--- /dev/null
+++ b/20231207/bsort-3a.c
@@ -0,0 +1,58 @@
+#include <stdio.h>
+#include <string.h>
+#include <unistd.h>
+
+int comparisons = 0;
+
+void display (char **name, int left, int right)
+{
+ printf ("\e[H\e[J");
+ for (int i = 0; name[i]; i++)
+ {
+ printf ("%s", name[i]);
+ if (i == left || i == right)
+ printf (" <--");
+ printf ("\n");
+ }
+ printf ("%d\n", comparisons);
+}
+
+int compare (char **name, int left, int right)
+{
+ int result = strcmp (name[left], name[right]);
+ comparisons++;
+ display (name, left, right);
+ usleep (200000);
+ return result;
+}
+
+void sort (char **name)
+{
+ int done = 0;
+ int sorted = 0;
+ while (name[sorted])
+ sorted++;
+ while (sorted > 0 && !done)
+ {
+ done = 1;
+ for (int i = 1; i < sorted; i++)
+ if (compare (name, i - 1, i) > 0)
+ {
+ done = 0;
+ char *temp = name[i - 1];
+ name[i - 1] = name[i];
+ name[i] = temp;
+ }
+ sorted--;
+ }
+}
+
+int main (void)
+{
+ char *name[] = { "Anna", "Berta", "Box", "Dieter", "Fritz", "Hans", "Heinrich", "Hugo",
+ "Lisa", "Maria", "Otto", "Peter", "Siegfried", "Thomas", "Ulrich",
+ "Zacharias", NULL };
+ sort (name);
+ display (name, -1, -1);
+ return 0;
+}
diff --git a/20231207/bsort-3b.c b/20231207/bsort-3b.c
new file mode 100644
index 0000000000000000000000000000000000000000..9795fe9a8ef59558bcf42f7bfe489f8b5f826521
--- /dev/null
+++ b/20231207/bsort-3b.c
@@ -0,0 +1,58 @@
+#include <stdio.h>
+#include <string.h>
+#include <unistd.h>
+
+int comparisons = 0;
+
+void display (char **name, int left, int right)
+{
+ printf ("\e[H\e[J");
+ for (int i = 0; name[i]; i++)
+ {
+ printf ("%s", name[i]);
+ if (i == left || i == right)
+ printf (" <--");
+ printf ("\n");
+ }
+ printf ("%d\n", comparisons);
+}
+
+int compare (char **name, int left, int right)
+{
+ int result = strcmp (name[left], name[right]);
+ comparisons++;
+ display (name, left, right);
+ usleep (200000);
+ return result;
+}
+
+void sort (char **name)
+{
+ int done = 0;
+ int sorted = 0;
+ while (name[sorted])
+ sorted++;
+ while (sorted > 0 && !done)
+ {
+ done = 1;
+ for (int i = 1; i < sorted; i++)
+ if (compare (name, i - 1, i) > 0)
+ {
+ done = 0;
+ char *temp = name[i - 1];
+ name[i - 1] = name[i];
+ name[i] = temp;
+ }
+ sorted--;
+ }
+}
+
+int main (void)
+{
+ char *name[] = { "Zacharias", "Ulrich", "Thomas", "Siegfried", "Peter", "Otto", "Maria",
+ "Lisa", "Hugo", "Heinrich", "Hans", "Fritz", "Dieter", "Box", "Berta",
+ "Anna", NULL };
+ sort (name);
+ display (name, -1, -1);
+ return 0;
+}
diff --git a/20231207/bsort-4.c b/20231207/bsort-4.c
new file mode 100644
index 0000000000000000000000000000000000000000..241270a46f4ffa005d252207d769c3c4059ed7e2
--- /dev/null
+++ b/20231207/bsort-4.c
@@ -0,0 +1,57 @@
+#include <stdio.h>
+#include <string.h>
+#include <unistd.h>
+
+int comparisons = 0;
+
+void display (char **name, int left, int right)
+{
+ printf ("\e[H\e[J");
+ for (int i = 0; name[i]; i++)
+ {
+ printf ("%s", name[i]);
+ if (i == left || i == right)
+ printf (" <--");
+ printf ("\n");
+ }
+ printf ("%d\n", comparisons);
+}
+
+int compare (char **name, int left, int right)
+{
+ int result = strcmp (name[left], name[right]);
+ comparisons++;
+ display (name, left, right);
+ usleep (200000);
+ return result;
+}
+
+void sort (char **name)
+{
+ int sorted = 0;
+ while (name[sorted])
+ sorted++;
+ while (sorted > 0)
+ {
+ int new_sorted = 0;
+ for (int i = 1; i < sorted; i++)
+ if (compare (name, i - 1, i) > 0)
+ {
+ new_sorted = i;
+ char *temp = name[i - 1];
+ name[i - 1] = name[i];
+ name[i] = temp;
+ }
+ sorted = new_sorted;
+ }
+}
+
+int main (void)
+{
+ char *name[] = { "Otto", "Lisa", "Anna", "Heinrich", "Siegfried", "Peter",
+ "Dieter", "Hugo", "Berta", "Maria", "Fritz", "Box", "Hans",
+ "Thomas", "Ulrich", "Zacharias", NULL };
+ sort (name);
+ display (name, -1, -1);
+ return 0;
+}
diff --git a/20231207/hanoi-32.c b/20231207/hanoi-32.c
new file mode 100644
index 0000000000000000000000000000000000000000..55e8d74db6d7284d6db225a6f8f3e08ab4efdc06
--- /dev/null
+++ b/20231207/hanoi-32.c
@@ -0,0 +1,58 @@
+#include <stdio.h>
+#include <error.h>
+
+#define DISKS 32
+
+int n[3], tower[3][DISKS];
+
+void display (void)
+{
+ printf ("\n");
+ for (int i = 0; i < 3; i++)
+ {
+ printf ("tower %d:", i);
+ for (int j = 0; j < n[i]; j++)
+ printf (" %d", tower[i][j]);
+ printf ("\n");
+ }
+}
+
+void move (int from, int to, int disks)
+{
+ if (disks == 1)
+ {
+ if (n[from] <= 0)
+ error (1, 0, "trying to move disk from empty tower");
+ if (n[to] > 0 && tower[to][n[to] - 1] < tower[from][n[from] - 1])
+ error (1, 0, "trying to move larger disk on smaller one");
+ tower[to][n[to]] = tower[from][n[from] - 1];
+ n[to]++;
+ n[from]--;
+ static int counter = 1;
+ if (counter++ >= 100000000)
+ {
+ display ();
+ counter = 1;
+ }
+ }
+ else
+ {
+ int help = 0 + 1 + 2 - from - to;
+ move (from, help, disks - 1);
+ move (from, to, 1);
+ move (help, to, disks - 1);
+ }
+}
+
+int main (void)
+{
+ n[0] = DISKS;
+ for (int i = 0; i < DISKS; i++)
+ tower[0][i] = DISKS - i;
+ n[1] = 0;
+ n[2] = 0;
+ display ();
+ move (0, 2, DISKS);
+ display ();
+ return 0;
+}
diff --git a/20231207/hp-20231207.pdf b/20231207/hp-20231207.pdf
index f1b861dbf29df728f937d9c68089cb0d57649ee3..19ef347b517567ceededc8726a63a5338b1b83f4 100644
Binary files a/20231207/hp-20231207.pdf and b/20231207/hp-20231207.pdf differ
diff --git a/20231207/hp-20231207.tex b/20231207/hp-20231207.tex
index 4bf45fea6f8b8815ed5fd7baa594135b39340e0f..45f0d25f40af750bb62e90acd4f634a5944c0651 100644
--- a/20231207/hp-20231207.tex
+++ b/20231207/hp-20231207.tex
@@ -248,41 +248,41 @@
}
\end{lstlisting}
\end{onlyenv}
-% \begin{onlyenv}<6->
-% \vspace{-5.0cm}
-% \hspace*{7.4cm}\begin{minipage}[t]{5cm}
-% 32 Scheiben:
-% \begin{lstlisting}[gobble=10,style=terminal]
-% $ ¡time ./hanoi-9b¿
-% ...
-% real 0m30,672s
-% user 0m30,662s
-% sys 0m0,008s
-% \end{lstlisting}
-% \pause[7]
-% \begin{itemize}
-% \arrowitem
-% etwas über 1 Minute\\
-% für 64 Scheiben
-% \end{itemize}
-% \pause
-% \vspace*{-0.5cm}
-% \begin{picture}(0,0)
-% \color{red}
-% \put(0,0){\makebox(0,0)[bl]{\tikz[line width=1pt]{\draw(0,0)--(4,0.8);}}}
-% \put(0,0.8){\makebox(0,0)[tl]{\tikz[line width=1pt]{\draw(0,0)--(4,-0.8);}}}
-% \end{picture}
-%
-% Für jede zusätzliche Scheibe\\verdoppelt sich die Rechenzeit!
-% % 30.672 * 2^32 / 3600 / 24 / 365.25 = 4174.43775518138261464750
-% \begin{itemize}
-% \arrowitem
-% $\frac{30,672\,\text{s}\,\cdot\,2^{32}}{3600\,\cdot\,24\,\cdot\,365,25} \approx 4174$
-% Jahre\\[\smallskipamount]
-% für 64 Scheiben
-% \end{itemize}
-% \end{minipage}
-% \end{onlyenv}
+ \begin{onlyenv}<6->
+ \vspace{-5.0cm}
+ \hspace*{7.4cm}\begin{minipage}[t]{5cm}
+ 32 Scheiben:
+ \begin{lstlisting}[gobble=10,style=terminal]
+ $ ¡time ./hanoi-9b¿
+ ...
+ real 0m30,672s
+ user 0m30,662s
+ sys 0m0,008s
+ \end{lstlisting}
+ \pause[7]
+ \begin{itemize}
+ \arrowitem
+ etwas über 1 Minute\\
+ für 64 Scheiben
+ \end{itemize}
+ \pause
+ \vspace*{-0.5cm}
+ \begin{picture}(0,0)
+ \color{red}
+ \put(0,0){\makebox(0,0)[bl]{\tikz[line width=1pt]{\draw(0,0)--(4,0.8);}}}
+ \put(0,0.8){\makebox(0,0)[tl]{\tikz[line width=1pt]{\draw(0,0)--(4,-0.8);}}}
+ \end{picture}
+
+ Für jede zusätzliche Scheibe\\verdoppelt sich die Rechenzeit!
+ % 30.672 * 2^32 / 3600 / 24 / 365.25 = 4174.43775518138261464750
+ \begin{itemize}
+ \arrowitem
+ $\frac{30,672\,\text{s}\,\cdot\,2^{32}}{3600\,\cdot\,24\,\cdot\,365,25} \approx 4174$
+ Jahre\\[\smallskipamount]
+ für 64 Scheiben
+ \end{itemize}
+ \end{minipage}
+ \end{onlyenv}
\end{onlyenv}
\end{frame}
diff --git a/20231207/hp-20231207.txt b/20231207/hp-20231207.txt
new file mode 100644
index 0000000000000000000000000000000000000000..0caaea428c61c64d54b0029851ee65baffce1831
--- /dev/null
+++ b/20231207/hp-20231207.txt
@@ -0,0 +1,20 @@
+x ^ 9 = x * x * x * x * x * x * x * x * x # 8 Multiplikationen
+
+ = ((x^2)^2)^2 * x # 4 Multiplikationen
+ `----v----'
+ x^8
+
+
+9 = 1001 binär
+
+ Bits von rechts nach links:
+
+ x x 1 --> damit multiplizieren
+
+ ^2 x^2 0 --> damit nicht multiplizieren
+
+ ^2 x^4 0 --> damit nicht multiplizieren
+
+ ^2 x^8 1 --> damit multiplizieren
+
+--> O(log n) statt O(n)
diff --git a/20231207/names.h b/20231207/names.h
new file mode 100644
index 0000000000000000000000000000000000000000..a265ff4141a2cc578d3f6f402822a2dbbd5cea90
--- /dev/null
+++ b/20231207/names.h
@@ -0,0 +1,50 @@
+"Michael", "Laura",
+"Elias", "Julia",
+"Luca", "Anna",
+"Liam", "Emma",
+"Alexander", "Lena",
+"Noah", "Vanessa",
+"Jonas", "Lea",
+"Marcel", "Mila",
+"Daniel", "Lisa",
+"David", "Lina",
+"Milan", "Sarah",
+"Julian", "Alina",
+"Linus", "Emilia",
+"Thomas", "Nina",
+"Samuel", "Elena",
+"Levin", "Lara",
+"Levi", "Melanie",
+"Jan", "Hannah",
+"Lukas", "Sandra",
+"Tim", "Leonie",
+"Patrick", "Sophie",
+"Marvin", "Mia",
+"Andreas", "Amelie",
+"Leon", "Selina",
+"Tobias", "Luisa",
+"Simon", "Maria",
+"Valentin", "Jana",
+"Robin", "Johanna",
+"Paul", "Marie",
+"Markus", "Milena",
+"Benjamin", "Melina",
+"Stefan", "Michelle",
+"Felix", "Emily",
+"Florian", "Renesmee",
+"Fabian", "Aylin",
+"Emil", "Jessica",
+"Aaron", "Franziska",
+"Manuel", "Jasmin",
+"Christian", "Fiona",
+"Dominik", "Sina",
+"Joshua", "Jennifer",
+"Moritz", "Claudia",
+"Sebastian", "Nicole",
+"Peter", "Annika",
+"Philipp", "Sophia",
+"Max", "Katharina",
+"Johannes", "Isabella",
+"Finn", "Nele",
+"Adrian", "Elisabeth",
+"Martin", "Pia",
diff --git a/20231207/qsort-1.c b/20231207/qsort-1.c
new file mode 100644
index 0000000000000000000000000000000000000000..c5431b853862e62812016f4fd3a031eeb0b5c9df
--- /dev/null
+++ b/20231207/qsort-1.c
@@ -0,0 +1,70 @@
+#include <stdio.h>
+#include <string.h>
+#include <unistd.h>
+
+int comparisons = 0;
+
+void display (char **name, char *pivot, int left, int right)
+{
+ printf ("\e[H\e[J");
+ for (int i = 0; name[i]; i++)
+ {
+ printf ("%s", name[i]);
+ if (name[i] == pivot)
+ printf (" <==");
+ else if (i == left || i == right)
+ printf (" <--");
+ printf ("\n");
+ }
+ printf ("%d\n", comparisons);
+}
+
+int compare (char **name, char *pivot, int left, int right)
+{
+ int result = strcmp (name[left], pivot);
+ comparisons++;
+ display (name, pivot, left, right);
+ usleep (200000);
+ return result;
+}
+
+void quicksort (char **name, int left, int right)
+{
+ int p = (left + right) / 2;
+ char *pivot = name[p];
+ int l = left;
+ int r = right;
+ while (l < r)
+ {
+ while (l < r && compare (name, pivot, l, r - 1) < 0)
+ l++;
+ while (l < r && compare (name, pivot, r - 1, l) > 0)
+ r--;
+ if (l < r)
+ {
+ char *temp = name[r - 1];
+ name[r - 1] = name[l];
+ name[l] = temp;
+ l++;
+ r--;
+ }
+ }
+}
+
+void sort (char **name)
+{
+ int r = 0;
+ while (name[r])
+ r++;
+ quicksort (name, 0, r);
+}
+
+int main (void)
+{
+ char *name[] = { "Otto", "Lisa", "Anna", "Heinrich", "Siegfried", "Peter",
+ "Dieter", "Hugo", "Berta", "Maria", "Fritz", "Box", "Hans",
+ "Thomas", "Ulrich", "Zacharias", NULL };
+ sort (name);
+ display (name, NULL, -1, -1);
+ return 0;
+}
diff --git a/20231207/qsort-2.c b/20231207/qsort-2.c
new file mode 100644
index 0000000000000000000000000000000000000000..cfdc2ec11a92a4292c9443e01453cce818e9e73a
--- /dev/null
+++ b/20231207/qsort-2.c
@@ -0,0 +1,72 @@
+#include <stdio.h>
+#include <string.h>
+#include <unistd.h>
+
+int comparisons = 0;
+
+void display (char **name, char *pivot, int left, int right)
+{
+ printf ("\e[H\e[J");
+ for (int i = 0; name[i]; i++)
+ {
+ printf ("%s", name[i]);
+ if (name[i] == pivot)
+ printf (" <==");
+ else if (i == left || i == right)
+ printf (" <--");
+ printf ("\n");
+ }
+ printf ("%d\n", comparisons);
+}
+
+int compare (char **name, char *pivot, int left, int right)
+{
+ int result = strcmp (name[left], pivot);
+ comparisons++;
+ display (name, pivot, left, right);
+ usleep (200000);
+ return result;
+}
+
+void quicksort (char **name, int left, int right)
+{
+ int p = (left + right) / 2;
+ char *pivot = name[p];
+ int l = left;
+ int r = right;
+ while (l < r)
+ {
+ while (l < r && compare (name, pivot, l, r - 1) < 0)
+ l++;
+ while (l < r && compare (name, pivot, r - 1, l) > 0)
+ r--;
+ if (l < r)
+ {
+ char *temp = name[r - 1];
+ name[r - 1] = name[l];
+ name[l] = temp;
+ l++;
+ r--;
+ }
+ }
+ if (l < right)
+ quicksort (name, l, right);
+}
+
+void sort (char **name)
+{
+ int r = 0;
+ while (name[r])
+ r++;
+ quicksort (name, 0, r);
+}
+
+int main (void)
+{
+ char *name[] = { "Otto", "Lisa", "Anna", "Heinrich", "Siegfried", "Peter",
+ "Dieter", "Hugo", "Berta", "Maria", "Fritz", "Box", "Hans",
+ "Thomas", "Ulrich", "Zacharias", NULL };
+ sort (name);
+ display (name, NULL, -1, -1);
+ return 0;
+}
diff --git a/20231207/qsort-3.c b/20231207/qsort-3.c
new file mode 100644
index 0000000000000000000000000000000000000000..e6b7d9909473af6d8c13d3745dc6b07e8ea75699
--- /dev/null
+++ b/20231207/qsort-3.c
@@ -0,0 +1,74 @@
+#include <stdio.h>
+#include <string.h>
+#include <unistd.h>
+
+int comparisons = 0;
+
+void display (char **name, char *pivot, int left, int right)
+{
+ printf ("\e[H\e[J");
+ for (int i = 0; name[i]; i++)
+ {
+ printf ("%s", name[i]);
+ if (name[i] == pivot)
+ printf (" <==");
+ else if (i == left || i == right)
+ printf (" <--");
+ printf ("\n");
+ }
+ printf ("%d\n", comparisons);
+}
+
+int compare (char **name, char *pivot, int left, int right)
+{
+ int result = strcmp (name[left], pivot);
+ comparisons++;
+ display (name, pivot, left, right);
+ usleep (200000);
+ return result;
+}
+
+void quicksort (char **name, int left, int right)
+{
+ int p = (left + right) / 2;
+ char *pivot = name[p];
+ int l = left;
+ int r = right;
+ while (l < r)
+ {
+ while (l < r && compare (name, pivot, l, r - 1) < 0)
+ l++;
+ while (l < r && compare (name, pivot, r - 1, l) > 0)
+ r--;
+ if (l < r)
+ {
+ char *temp = name[r - 1];
+ name[r - 1] = name[l];
+ name[l] = temp;
+ l++;
+ r--;
+ }
+ }
+ if (r > left)
+ quicksort (name, left, r);
+ if (l < right)
+ quicksort (name, l, right);
+}
+
+void sort (char **name)
+{
+ int r = 0;
+ while (name[r])
+ r++;
+ quicksort (name, 0, r);
+}
+
+int main (void)
+{
+ char *name[] = { "Otto", "Lisa", "Anna", "Heinrich", "Siegfried", "Peter",
+ "Dieter", "Hugo", "Berta", "Maria", "Fritz", "Box", "Hans",
+ "Thomas", "Ulrich", "Zacharias", NULL };
+ sort (name);
+ display (name, NULL, -1, -1);
+ return 0;
+}
diff --git a/20231207/qsort-3a.c b/20231207/qsort-3a.c
new file mode 100644
index 0000000000000000000000000000000000000000..d3e757ee78e451a57769b29438713ebe5202c2b4
--- /dev/null
+++ b/20231207/qsort-3a.c
@@ -0,0 +1,74 @@
+#include <stdio.h>
+#include <string.h>
+#include <unistd.h>
+
+int comparisons = 0;
+
+void display (char **name, char *pivot, int left, int right)
+{
+ printf ("\e[H\e[J");
+ for (int i = 0; name[i]; i++)
+ {
+ printf ("%s", name[i]);
+ if (name[i] == pivot)
+ printf (" <==");
+ else if (i == left || i == right)
+ printf (" <--");
+ printf ("\n");
+ }
+ printf ("%d\n", comparisons);
+}
+
+int compare (char **name, char *pivot, int left, int right)
+{
+ int result = strcmp (name[left], pivot);
+ comparisons++;
+ display (name, pivot, left, right);
+ usleep (200000);
+ return result;
+}
+
+void quicksort (char **name, int left, int right)
+{
+ int p = (left + right) / 2;
+ char *pivot = name[p];
+ int l = left;
+ int r = right;
+ while (l < r)
+ {
+ while (l < r && compare (name, pivot, l, r - 1) < 0)
+ l++;
+ while (l < r && compare (name, pivot, r - 1, l) > 0)
+ r--;
+ if (l < r)
+ {
+ char *temp = name[r - 1];
+ name[r - 1] = name[l];
+ name[l] = temp;
+ l++;
+ r--;
+ }
+ }
+ if (r > left)
+ quicksort (name, left, r);
+ if (l < right)
+ quicksort (name, l, right);
+}
+
+void sort (char **name)
+{
+ int r = 0;
+ while (name[r])
+ r++;
+ quicksort (name, 0, r);
+}
+
+int main (void)
+{
+ char *name[] = { "Anna", "Berta", "Box", "Dieter", "Fritz", "Hans", "Heinrich", "Hugo",
+ "Lisa", "Maria", "Otto", "Peter", "Siegfried", "Thomas", "Ulrich",
+ "Zacharias", NULL };
+ sort (name);
+ display (name, NULL, -1, -1);
+ return 0;
+}
diff --git a/20231207/qsort-3b.c b/20231207/qsort-3b.c
new file mode 100644
index 0000000000000000000000000000000000000000..0bafef40b8500bed175ab2b53c28ea97494bfe7b
--- /dev/null
+++ b/20231207/qsort-3b.c
@@ -0,0 +1,74 @@
+#include <stdio.h>
+#include <string.h>
+#include <unistd.h>
+
+int comparisons = 0;
+
+void display (char **name, char *pivot, int left, int right)
+{
+ printf ("\e[H\e[J");
+ for (int i = 0; name[i]; i++)
+ {
+ printf ("%s", name[i]);
+ if (name[i] == pivot)
+ printf (" <==");
+ else if (i == left || i == right)
+ printf (" <--");
+ printf ("\n");
+ }
+ printf ("%d\n", comparisons);
+}
+
+int compare (char **name, char *pivot, int left, int right)
+{
+ int result = strcmp (name[left], pivot);
+ comparisons++;
+ display (name, pivot, left, right);
+ usleep (200000);
+ return result;
+}
+
+void quicksort (char **name, int left, int right)
+{
+ int p = (left + right) / 2;
+ char *pivot = name[p];
+ int l = left;
+ int r = right;
+ while (l < r)
+ {
+ while (l < r && compare (name, pivot, l, r - 1) < 0)
+ l++;
+ while (l < r && compare (name, pivot, r - 1, l) > 0)
+ r--;
+ if (l < r)
+ {
+ char *temp = name[r - 1];
+ name[r - 1] = name[l];
+ name[l] = temp;
+ l++;
+ r--;
+ }
+ }
+ if (r > left)
+ quicksort (name, left, r);
+ if (l < right)
+ quicksort (name, l, right);
+}
+
+void sort (char **name)
+{
+ int r = 0;
+ while (name[r])
+ r++;
+ quicksort (name, 0, r);
+}
+
+int main (void)
+{
+ char *name[] = { "Zacharias", "Ulrich", "Thomas", "Siegfried", "Peter", "Otto", "Maria",
+ "Lisa", "Hugo", "Heinrich", "Hans", "Fritz", "Dieter", "Box", "Berta",
+ "Anna", NULL };
+ sort (name);
+ display (name, NULL, -1, -1);
+ return 0;
+}
diff --git a/20231207/sort-0.c b/20231207/sort-0.c
new file mode 100644
index 0000000000000000000000000000000000000000..70e0e717cbfd42a27bf90f419c216fa18b0783c7
--- /dev/null
+++ b/20231207/sort-0.c
@@ -0,0 +1,16 @@
+#include <stdio.h>
+
+int find_first (char **name)
+{
+ return 2;
+}
+
+int main (void)
+{
+ char *name[] = { "Otto", "Lisa", "Anna", "Heinrich", "Siegfried", "Peter",
+ "Dieter", "Hugo", "Berta", "Maria", "Fritz", "Box", "Hans",
+ "Thomas", "Ulrich", "Zacharias", NULL };
+ int first = find_first (name);
+ printf ("%s\n", name[first]);
+ return 0;
+}
diff --git a/20231207/sort-1.c b/20231207/sort-1.c
new file mode 100644
index 0000000000000000000000000000000000000000..3f009d45657f84e462db48a67fa22821819216ad
--- /dev/null
+++ b/20231207/sort-1.c
@@ -0,0 +1,21 @@
+#include <stdio.h>
+#include <string.h>
+
+int find_first (char **name)
+{
+ int first = 0;
+ for (int i = 1; name[i]; i++)
+ if (strcmp (name[i], name[first]) < 0)
+ first = i;
+ return first;
+}
+
+int main (void)
+{
+ char *name[] = { "Otto", "Lisa", "Anna", "Heinrich", "Siegfried", "Peter",
+ "Dieter", "Hugo", "Berta", "Maria", "Fritz", "Box", "Hans",
+ "Thomas", "Ulrich", "Zacharias", NULL };
+ int first = find_first (name);
+ printf ("%s\n", name[first]);
+ return 0;
+}
diff --git a/20231207/sort-1a.c b/20231207/sort-1a.c
new file mode 100644
index 0000000000000000000000000000000000000000..e60f10393cf93897697f888c7ec0107c5313edfe
--- /dev/null
+++ b/20231207/sort-1a.c
@@ -0,0 +1,21 @@
+#include <stdio.h>
+#include <string.h>
+
+int find_first (char **name)
+{
+ int first = 0;
+ for (int i = 1; name[i]; i++)
+ if (strcmp (name[i], name[first]) < 0)
+ first = i;
+ return first;
+}
+
+int main (void)
+{
+ char *name[] = { "otto", "Lisa", "Anna", "Heinrich", "Siegfried", "Peter",
+ "Dieter", "Hugo", "Berta", "Maria", "Fritz", "Box", "Hans",
+ "Thomas", "Ulrich", "Zacharias", NULL };
+ int first = find_first (name);
+ printf ("%s\n", name[first]);
+ return 0;
+}
diff --git a/20231207/sort-2.c b/20231207/sort-2.c
new file mode 100644
index 0000000000000000000000000000000000000000..638e6e2caa670ceace0a854d0827292dfcb59ca5
--- /dev/null
+++ b/20231207/sort-2.c
@@ -0,0 +1,46 @@
+#include <stdio.h>
+#include <string.h>
+#include <unistd.h>
+
+int comparisons = 0;
+
+void display (char **name, int left, int right)
+{
+ printf ("\e[H\e[J");
+ for (int i = 0; name[i]; i++)
+ {
+ printf ("%s", name[i]);
+ if (i == left || i == right)
+ printf (" <--");
+ printf ("\n");
+ }
+ printf ("%d\n", comparisons);
+}
+
+int compare (char **name, int left, int right)
+{
+ int result = strcmp (name[left], name[right]);
+ comparisons++;
+ display (name, left, right);
+ usleep (200000);
+ return result;
+}
+
+int find_first (char **name)
+{
+ int first = 0;
+ for (int i = 1; name[i]; i++)
+ if (compare (name, i, first) < 0)
+ first = i;
+ return first;
+}
+
+int main (void)
+{
+ char *name[] = { "Otto", "Lisa", "Anna", "Heinrich", "Siegfried", "Peter",
+ "Dieter", "Hugo", "Berta", "Maria", "Fritz", "Box", "Hans",
+ "Thomas", "Ulrich", "Zacharias", NULL };
+ int first = find_first (name);
+ display (name, first, -1);
+ return 0;
+}
diff --git a/20231207/sort-3.c b/20231207/sort-3.c
new file mode 100644
index 0000000000000000000000000000000000000000..430a6fc0e95fcb9bc225e3572566c8d187016130
--- /dev/null
+++ b/20231207/sort-3.c
@@ -0,0 +1,46 @@
+#include <stdio.h>
+#include <string.h>
+#include <unistd.h>
+
+int comparisons = 0;
+
+void display (char **name, int left, int right)
+{
+ printf ("\e[H\e[J");
+ for (int i = 0; name[i]; i++)
+ {
+ printf ("%s", name[i]);
+ if (i == left || i == right)
+ printf (" <--");
+ printf ("\n");
+ }
+ printf ("%d\n", comparisons);
+}
+
+int compare (char **name, int left, int right)
+{
+ int result = strcmp (name[left], name[right]);
+ comparisons++;
+ display (name, left, right);
+ usleep (200000);
+ return result;
+}
+
+int find_first (char **name, int i0)
+{
+ int first = i0;
+ for (int i = i0 + 1; name[i]; i++)
+ if (compare (name, i, first) < 0)
+ first = i;
+ return first;
+}
+
+int main (void)
+{
+ char *name[] = { "Otto", "Lisa", "Anna", "Heinrich", "Siegfried", "Peter",
+ "Dieter", "Hugo", "Berta", "Maria", "Fritz", "Box", "Hans",
+ "Thomas", "Ulrich", "Zacharias", NULL };
+ int first = find_first (name, 0);
+ display (name, first, -1);
+ return 0;
+}
diff --git a/20231207/sort-4.c b/20231207/sort-4.c
new file mode 100644
index 0000000000000000000000000000000000000000..19d4f416a2d30c5181ad289fe1d0dcba91ee81cf
--- /dev/null
+++ b/20231207/sort-4.c
@@ -0,0 +1,59 @@
+#include <stdio.h>
+#include <string.h>
+#include <unistd.h>
+
+int comparisons = 0;
+
+void display (char **name, int left, int right)
+{
+ printf ("\e[H\e[J");
+ for (int i = 0; name[i]; i++)
+ {
+ printf ("%s", name[i]);
+ if (i == left || i == right)
+ printf (" <--");
+ printf ("\n");
+ }
+ printf ("%d\n", comparisons);
+}
+
+int compare (char **name, int left, int right)
+{
+ int result = strcmp (name[left], name[right]);
+ comparisons++;
+ display (name, left, right);
+ usleep (200000);
+ return result;
+}
+
+int find_first (char **name, int i0)
+{
+ int first = i0;
+ for (int i = i0 + 1; name[i]; i++)
+ if (compare (name, i, first) < 0)
+ first = i;
+ return first;
+}
+
+void sort (char **name)
+{
+ int sorted = 0;
+ while (name[sorted])
+ {
+ int first = find_first (name, sorted);
+ char *temp = name[sorted];
+ name[sorted] = name[first];
+ name[first] = temp;
+ sorted++;
+ }
+}
+
+int main (void)
+{
+ char *name[] = { "Otto", "Lisa", "Anna", "Heinrich", "Siegfried", "Peter",
+ "Dieter", "Hugo", "Berta", "Maria", "Fritz", "Box", "Hans",
+ "Thomas", "Ulrich", "Zacharias", NULL };
+ sort (name);
+ display (name, -1, -1);
+ return 0;
+}
diff --git a/20231207/sort-4a.c b/20231207/sort-4a.c
new file mode 100644
index 0000000000000000000000000000000000000000..8312d2ba96ee6afe3dd1d50a440028bba6386e00
--- /dev/null
+++ b/20231207/sort-4a.c
@@ -0,0 +1,59 @@
+#include <stdio.h>
+#include <string.h>
+#include <unistd.h>
+
+int comparisons = 0;
+
+void display (char **name, int left, int right)
+{
+ printf ("\e[H\e[J");
+ for (int i = 0; name[i]; i++)
+ {
+ printf ("%s", name[i]);
+ if (i == left || i == right)
+ printf (" <--");
+ printf ("\n");
+ }
+ printf ("%d\n", comparisons);
+}
+
+int compare (char **name, int left, int right)
+{
+ int result = strcmp (name[left], name[right]);
+ comparisons++;
+ display (name, left, right);
+ usleep (200000);
+ return result;
+}
+
+int find_first (char **name, int i0)
+{
+ int first = i0;
+ for (int i = i0 + 1; name[i]; i++)
+ if (compare (name, i, first) < 0)
+ first = i;
+ return first;
+}
+
+void sort (char **name)
+{
+ int sorted = 0;
+ while (name[sorted])
+ {
+ int first = find_first (name, sorted);
+ char *temp = name[sorted];
+ name[sorted] = name[first];
+ name[first] = temp;
+ sorted++;
+ }
+}
+
+int main (void)
+{
+ char *name[] = { "Anna", "Berta", "Box", "Dieter", "Fritz", "Hans", "Heinrich", "Hugo",
+ "Lisa", "Maria", "Otto", "Peter", "Siegfried", "Thomas", "Ulrich",
+ "Zacharias", NULL };
+ sort (name);
+ display (name, -1, -1);
+ return 0;
+}
diff --git a/20231207/sort-5.c b/20231207/sort-5.c
new file mode 100644
index 0000000000000000000000000000000000000000..f0742bc8665d0b13edf4ad4ad3fe4790c1e6b929
--- /dev/null
+++ b/20231207/sort-5.c
@@ -0,0 +1,60 @@
+#include <stdio.h>
+#include <string.h>
+#include <unistd.h>
+
+int comparisons = 0;
+
+void display (char **name, int left, int right)
+{
+ printf ("\e[H\e[J");
+ for (int i = 0; name[i]; i++)
+ {
+ printf ("%s", name[i]);
+ if (i == left || i == right)
+ printf (" <--");
+ printf ("\n");
+ }
+ printf ("%d\n", comparisons);
+}
+
+int compare (char **name, int left, int right)
+{
+ int result = strcmp (name[left], name[right]);
+ comparisons++;
+ display (name, left, right);
+ usleep (200);
+ return result;
+}
+
+int find_first (char **name, int i0)
+{
+ int first = i0;
+ for (int i = i0 + 1; name[i]; i++)
+ if (compare (name, i, first) < 0)
+ first = i;
+ return first;
+}
+
+void sort (char **name)
+{
+ int sorted = 0;
+ while (name[sorted])
+ {
+ int first = find_first (name, sorted);
+ char *temp = name[sorted];
+ name[sorted] = name[first];
+ name[first] = temp;
+ sorted++;
+ }
+}
+
+int main (void)
+{
+ char *name[] = {
+ #include "names.h"
+ NULL
+ };
+ sort (name);
+ display (name, -1, -1);
+ return 0;
+}
diff --git a/20231207/sort-6.c b/20231207/sort-6.c
new file mode 100644
index 0000000000000000000000000000000000000000..94a1a16abfacda7bb728f8d3317cd00b4cf8ccde
--- /dev/null
+++ b/20231207/sort-6.c
@@ -0,0 +1,60 @@
+#include <stdio.h>
+#include <string.h>
+#include <unistd.h>
+
+int comparisons = 0;
+
+void display (char **name, int left, int right)
+{
+ printf ("\e[H\e[J");
+ for (int i = 0; name[i]; i++)
+ {
+ printf ("%s", name[i]);
+ if (i == left || i == right)
+ printf (" <--");
+ printf ("\n");
+ }
+ printf ("%d\n", comparisons);
+}
+
+int compare (char **name, int left, int right)
+{
+ int result = strcmp (name[left], name[right]);
+ comparisons++;
+// display (name, left, right);
+// usleep (200);
+ return result;
+}
+
+int find_first (char **name, int i0)
+{
+ int first = i0;
+ for (int i = i0 + 1; name[i]; i++)
+ if (compare (name, i, first) < 0)
+ first = i;
+ return first;
+}
+
+void sort (char **name)
+{
+ int sorted = 0;
+ while (name[sorted])
+ {
+ int first = find_first (name, sorted);
+ char *temp = name[sorted];
+ name[sorted] = name[first];
+ name[first] = temp;
+ sorted++;
+ }
+}
+
+int main (void)
+{
+ char *name[] = {
+ #include "names.h"
+ NULL
+ };
+ sort (name);
+ display (name, -1, -1);
+ return 0;
+}
diff --git a/20231207/sort-7.c b/20231207/sort-7.c
new file mode 100644
index 0000000000000000000000000000000000000000..46132dd247a061dda0e5ebade9c5b818a1a74fcb
--- /dev/null
+++ b/20231207/sort-7.c
@@ -0,0 +1,53 @@
+#include <stdio.h>
+#include <string.h>
+#include <unistd.h>
+
+int comparisons = 0;
+
+void display (char **name, int left, int right)
+{
+ printf ("\e[H\e[J");
+ for (int i = 0; name[i]; i++)
+ {
+ printf ("%s", name[i]);
+ if (i == left || i == right)
+ printf (" <--");
+ printf ("\n");
+ }
+ printf ("%d\n", comparisons);
+}
+
+int compare (char **name, int left, int right)
+{
+ int result = strcmp (name[left], name[right]);
+ comparisons++;
+ display (name, left, right);
+ usleep (200000);
+ return result;
+}
+
+void sort (char **name)
+{
+ int sorted = 0;
+ while (name[sorted])
+ {
+ int first = sorted;
+ for (int i = sorted + 1; name[i]; i++)
+ if (compare (name, i, first) < 0)
+ first = i;
+ char *temp = name[sorted];
+ name[sorted] = name[first];
+ name[first] = temp;
+ sorted++;
+ }
+}
+
+int main (void)
+{
+ char *name[] = { "Otto", "Lisa", "Anna", "Heinrich", "Siegfried", "Peter",
+ "Dieter", "Hugo", "Berta", "Maria", "Fritz", "Box", "Hans",
+ "Thomas", "Ulrich", "Zacharias", NULL };
+ sort (name);
+ display (name, -1, -1);
+ return 0;
+}