딱 보니 map을 쓰면 좋을 것 같아 써버렸다!
#include <iostream>
#include <map>
using namespace std;
map<string, string> m;
int main()
{
cin.tie(NULL);
cout.tie(NULL);
ios::sync_with_stdio(false);
int N, M;
cin >> N >> M;
for (int i = 1; i <= N; i++)
{
string ad, pass;
cin >> ad >> pass;
m.insert(make_pair(ad, pass));
}
for (int k = 0; k < M; k++)
{
string tmp;
cin >> tmp;
cout << m[tmp] << '\n';
}
}