#include <stdio.h>                                                              
#include <stdlib.h>                                                             
#include <string.h>                                                             
                                                                                
#define TRUE         0                                                          
#define FALSE       -1                                                          
                                                                                
void main(void){                                                                
    char str[] = "MY PERSONAL COMPUTER";                                        
    char* ptr;                                                                  
    int pos;                                                                    
                                                                                
    ptr = strstr(str, "SON");                                                   
    if(ptr != NULL){                                                            
       pos = (int)(ptr - str);                                                  
       printf("FOUND AT %d\n", pos);                                            
    }                                                                           
    getchar();                                                                  
}