String::rfind

The function returns the position of the target string (key) that was last matched in the source string
If no matching position is found then return String::npos, which is an unsigned shaped number that can be printed to see

String::rfind#include "stdafx.h" #include <iostream> #include <string> #include <cstddef>using namespace Std;int Main (int argc, char* argv[]) {string str ("I love-you-do-love me."); String key ("Love"): size_t found = Str.rfind (key), if (Found!=string::npos) str.replace (Found,key.length (), "like");// Cout<<string::npos<<endl;cout << str <<endl;return 0;}

　　

The result of the final operation:

String::rfind