1  #include <stdio.h>
       2  g ()
       3  {
       4    return '\n';
       5  }
       6  
       7  f ()
       8  {
       9    char s[] = "abcedfg012345";
      10    char *sp = s + 12;
      11  
      12    switch (g ())
      13      {
      14        case '\n':
      15          break;
      16      }
      17  
      18    while (*--sp == '0')
      19      ;
      20    sprintf (sp + 1, "X");
      21  
      22    if (s[12] != 'X')
      23      abort ();
      24  }
      25  
      26  main ()
      27  {
      28    f ();
      29    exit (0);
      30  }