/* ---------
   KMP failure function
   ---------------------- */

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

int f[100];

void mk_f(char *P)
{
   int i, j, m;

   m = strlen(P);

   f[0] = 0;
   i = 1;
   j = 0;

   while ( i < m )
   {
      if ( P[i] == P[j] )
      {
	 f[i] = j+1;

	 i++;
	 j++;
      }
      else
      {
	 if ( j == 0 )
 	 {
	    f[i] = 0;
	    i++;
	 } 
	 else
	 {
	    j = f[j-1];
	 }
      }
   }
}


int main(int argc, char **argv)
{
   int i, len;

   if ( argc <= 1 )
   {
      printf("Usage: %s Pattern\n\n", argv[0]);
      printf("   Program computes KMP failure function\n\n\n");

      exit(1);
   }

   mk_f( argv[1] );

   len = strlen(argv[1]);
   for (i = 0; i < len; i++ )
   {
      printf("f(%d) = %d\n", i, f[i]);
   }
}