string::rfind

string (1)	size_t rfind (const string& str, size_t pos = npos) const noexcept;
c-string (2)	size_t rfind (const char* s, size_t pos = npos) const;
buffer (3)	size_t rfind (const char* s, size_t pos, size_t n) const;
character (4)	size_t rfind (char c, size_t pos = npos) const noexcept;:

#include <iostream>
#include <string>
using namespace std;
int main()
{
string s1 = "lyy is mulushu, but lyy is quiet";
string s2 = "lyy";
const char *s3 = "lyy";
cout << s1.rfind(s2) << endl;
cout << s1.rfind(s2, 30) << endl;
cout << s1.rfind(s3, 40, 2) << endl;
cout << s1.rfind(s3, 40, 3) << endl;
cout << s1.rfind('t', 20) << endl;
return 0;
}