c++ string startwith方法使用

#include <iostream>

using namespace std;

int main()

{

string s("hello, world");

string head("hello");

string tail("ld");

bool startwith = s.compare(0, head.size(), head) == 0;

cout << boolalpha << startwith << endl;

bool endwith = s.compare(s.size() - tail.size(), tail.size(), tail) == 0;

cout << boolalpha << endwith << endl;

}