#include <stdio.h>
#include <stdlib.h>
#include <string.h>

int main()
{
  char buf[50];
  char *x, *y;
  int i;

  x = buf+5;
  y = buf+10;

  strcpy(buf, "012345678");
  strcat(x, "Fred");
  printf("0: '%s'\n", buf);
  printf("1: '%s'\n", x);

  strcpy(buf, "AABBCCDDEE");
  for (i = 0; i < 10; i += 2) buf[i] += (i/2); 
  printf("2: '%s'\n", buf);

  strcpy(buf, "JJKKLLMMNNOOPPQQRRSS");
  strcpy(y,   "AABB");
  strcpy(x,   "UVWXYZ");
  printf("3: '%s'\n", buf);
  printf("4: '%s'\n", buf+4);
  printf("5: '%s'\n", buf+8);
  printf("6: '%s'\n", buf+12);
  printf("7: '%s'\n", buf+16);

  strcpy(buf, "0123456789ABCDEFGHIJ");
  printf("8: %c\n", *(buf+(y-x)));
  y += (buf[4] - buf[0]);
  printf("9: %c\n", y[3]);
  return 0;
}