Lehrmaterialien, Beispiel-Programme und Übungsaufgaben 29.10.2018

20181029/array-vs-pointer-1.c

+#include <stdio.h>
+
+int main (void)
+{
+  char h[] = "Hello!\n";
+  h[1] = 'a';
+  printf ("%s", h);
+  return 0;
+}

20181029/array-vs-pointer-10.c

+#include <stdio.h>
+
+int main (void)
+{
+  char *h = "Hello!\n";
+  while (*h)
+    printf ("%c", (*h)++);
+  return 0;
+}

20181029/array-vs-pointer-2.c

+#include <stdio.h>
+
+int main (void)
+{
+  char *h = "Hello!\n";
+  h[1] = 'a';
+  printf ("%s", h);
+  return 0;
+}

20181029/array-vs-pointer-3.c

+#include <stdio.h>
+
+int main (void)
+{
+  char hello[] = "Hello!\n";
+  char *h = hello;
+  h[1] = 'a';
+  printf ("%s", h);
+  return 0;
+}

20181029/array-vs-pointer-4.c

+#include <stdio.h>
+
+int main (void)
+{
+  char h[] = "Hello!\n";
+  int i = 0;
+  while (h[i])
+    printf ("%c", h[i++]);
+  return 0;
+}

20181029/array-vs-pointer-5.c

+#include <stdio.h>
+
+int main (void)
+{
+  char *h = "Hello!\n";
+  int i = 0;
+  while (h[i])
+    printf ("%c", h[i++]);
+  return 0;
+}

20181029/array-vs-pointer-6.c

+#include <stdio.h>
+
+int main (void)
+{
+  char h[] = "Hello!\n";
+  printf ("%c\n", *h);
+  return 0;
+}

20181029/array-vs-pointer-7.c

+#include <stdio.h>
+
+int main (void)
+{
+  char h[] = "Hello!\n";
+  while (*h)
+    printf ("%c", *h++);
+  return 0;
+}

20181029/array-vs-pointer-8.c

+#include <stdio.h>
+
+int main (void)
+{
+  char h[] = "Hello!\n";
+  while (*h)
+    printf ("%c", (*h)++);
+  return 0;
+}

20181029/array-vs-pointer-9.c

+#include <stdio.h>
+
+int main (void)
+{
+  char h[] = "Hello!\n";
+  while (*h)
+    printf ("%c", *h + 1);
+  return 0;
+}

20181029/ascii-1.c

+#include <stdio.h>
+
+int main (void)
+{
+  printf ("Der Buchstabe lautet: %c\n", 1117);
+  return 0;
+}

20181029/ascii-2.c

+#include <stdio.h>
+
+int main (void)
+{
+  printf ("Der Buchstabe lautet: %c\n", 1117);
+  printf ("Die Zahl lautet: %d\n", ']');
+  return 0;
+}

20181029/ascii-3.c

+#include <stdio.h>
+
+int main (void)
+{
+  printf ("Der Buchstabe lautet: %c\n", 1117);
+  printf ("Die Zahl lautet: %d\n", ']');
+  printf ("Der Buchstabe als Hexadezimalzahl lautet: %x\n", 1117);
+  printf ("Die Zahl in hexadezimal lautet: %x\n", ']');
+  return 0;
+}

20181029/aufgabe-1.c

+int fun_1 (char *s1, char *s2)
+{
+  int result = 1;
+  for (int i = 0; s1[i] && s2[i]; i++)
+    if (s1[i] != s2[i])
+      result = 0;
+  return result;
+}

20181029/aufgabe-2.c

+#include <stdio.h>
+
+int main (void)
+{
+  int n, i, divisors;
+  for (n = 0; n < 100; n++)
+    divisors = 0;
+    for (i = 0; i < n; i++)
+      if (n % i == 0)
+        divisors++;
+    if (divisors = 2)
+      printf ("%d ist eine Primzahl.\n", n);
+  return 0;
+}

20181029/fhello.txt

+Hello, world!

20181029/files-1.c

+#include <stdio.h>
+
+int main (void)
+{
+  FILE *f = fopen ("fhello.txt", "w");
+  fprintf (f, "Hello, world!\n");
+  fclose (f);
+  return 0;
+}

20181029/files-2.c

+#include <stdio.h>
+
+int main (void)
+{
+  FILE *f = fopen ("fhello.txt", "w");
+  if (f)
+    {
+      fprintf (f, "Hello, world!\n");
+      fclose (f);
+    }
+  return 0;
+}

20181029/files-3.c

+#include <stdio.h>
+#include <errno.h>
+
+int main (void)
+{
+  FILE *f = fopen ("fhello.txt", "w");
+  if (f)
+    {
+      fprintf (f, "Hello, world!\n");
+      fclose (f);
+    }
+  else
+    fprintf (stderr, "error #%d\n", errno);
+  return 0;
+}

20181029/files-4.c

+#include <stdio.h>
+#include <errno.h>
+#include <string.h>
+
+int main (void)
+{
+  FILE *f = fopen ("fhello.txt", "w");
+  if (f)
+    {
+      fprintf (f, "Hello, world!\n");
+      fclose (f);
+    }
+  else
+    {
+      char *msg = strerror (errno);
+      fprintf (stderr, "%s\n", msg);
+    }
+  return 0;
+}