c++ - Using std::search to find multiple occurrence of pattern -

i want use function search or other similar function find multiple occurrence of given pattern.

this code:

#include <cstring>   #include <iostream>  #include <iomanip>   #include <set> #include <list> #include <vector> #include <map>    #include <algorithm> #include <functional> using namespace std;  int main () {   std::vector<int> haystack;    string = "abcabcabc";   string b = "abc";   string::iterator it;   = search(a.begin(),a.end(),b.begin(),b.end());    if(it!=a.end()){       cout << it-a.begin()<<endl;   }    return 0; } 

this code return 0 first occurrence of pattern "abc" , return 0, 3, 6. of indexes in original string pattern begins.

thank help.

for(size_t pos=a.find(b,0); pos!=std::string::npos; pos=a.find(b,pos+1)) {     std::cout << pos << std::endl; }     

this uses std::basic_string::find (ref) directly find starting position of substring.