#include <iostream.h>
const char EOS = '\0';
const int  MAXPATLEN = 30;


void computePrefix(char * pattern, int overlap[])
{
    int i,j;

    i = 0;
    j = overlap[0] = -1;
    for (i = 0; pattern[i] != '\0'; i ++)
    {
      overlap[i + 1] = overlap[i] + 1;
      while (overlap[i + 1] > 0 &&
               pattern[i] != pattern[overlap[i + 1] - 1])
         overlap[i + 1] = overlap[overlap[i + 1] - 1] + 1;
    }

}
char * search(char * pat, char * text)
{
    int next[MAXPATLEN];
    int i, j, o;
    int n = strlen(text);
    int max(int, int);

    if (*pat == EOS)
	return text;
    computePrefix(pat, next);
    for (i = 0; pat[i] != 0; i ++)
	cout << next[i] << " ";
    cout << endl;

    i = 0;
    o = 0;
    while (i < n)
    {
	for (j = 0; text[i + j] != '\0' && pat[j] != '\0' && 
		 text[i + j] == pat[j]; j ++);
	if (pat[j] == '\0')
	    return &(text[i]);
	o = next[j];
	i = i + max(1, j - o);
    }
    return NULL;
}

int max(int i, int j)
{
    if (i > j)
	return i;
    else
	return j;
}