1 #include <iostream>
     2 #include <cstring>
     3 
     4 using namespace std;
     5 
     6 int main ()
     7 {
     8 
     9   char str1[] = "mmmmgoodmmmmmgood" ;
    10   char str2[] = "mmmgood" ;
    11 
    12 
    13   char * p =  str1 ;
    14   char * p2 = str2 ;
    15   char * start = NULL ;
    16 
    17   while ( *p != '\0' && *p2 != '\0')
    18   {
    19       if( *p == *p2){
    20          p2++ ;
    21          if( start == NULL) start = p ;
    22          p++ ;
    23       }
    24       else if ( start != NULL){
    25          //reset
    26          p2 = str2 ;
    27          start = NULL ;
    28      }
    29      else
    30         p++ ;
    31   }
    32 
    33 
    34   cout << "result is " <<  start << endl;
    35 
    36 }
    37