main.cpp

#include <string>
#include <iostream>

using namespace std;

int main() {
  string s = "lollero";
  string t = "lerolo";
  auto si = s.begin() + 3;
  auto ti = t.begin();

  while (true) {
    if (si == s.end()) {
      si = s.begin();
    }

    if (ti == t.end()) {
      cout << "match";
      break;
    }

    if (*si != *ti) {
      cout << "mismatch";
      break;
    }

    si++;
    ti++;
  }
}