demkitugiong nhau

#include<iostream>
#include<string>
using namespace std;
int giongnhau(string s1, string s2) {
	int dem = 0;
	for (int i = 0; i < s1.size(); i++) {
		for (int j = 0; j < s2.size(); j++) {
			if (s1[i] == s2[j]) {
				 dem = dem + 1;
			}
		}
	}
	return dem;
}
void main() {
	string s1, s2;

	cout << giongnhau("abcde", "abee");
	system("pause>null");

}