题解（CSP-J 2024）

#include <bits/stdc++.h>
using namespace std;
const int maxn = 60;
int n;
struct node{
    char type;
    char num;
}a[maxn];
int main(){
    cin >> n;
    int cnt = 0;
    for(int i = 1; i <= n; i++){
        string s;
        cin >> s;
        a[i].type = s[0];
        a[i].num = s[1];
        bool f = true;
        for(int j = 1; j < i; j++){
            if(a[j].type == a[i].type && a[j].num == a[i].num){
                f = false;
            }
        }
        if(f) cnt++;
    }
    cout << 52 - cnt;
    return 0;
}