umap 秒了：

#include<bits/stdc++.h>
#define ll long long
using namespace std;
ll n, ans = 0;
unordered_map<string, bool> Map;
int main() {
    ios::sync_with_stdio(false);
    cin.tie(0), cout.tie(0);
    cin >> n;
    for(int i = 1; i <= n; i++) {
        string s; cin >> s;
        if(!Map[s]) Map[s] = true, ans++;
        else continue;
    }
    cout << ans << endl;
    return 0;
}