题解 | 牛牛的考试

#include <algorithm>
#include <iostream>
#include <utility>
using namespace std;

int main() {
    int n;
    pair<int, char> arr[4];
    cin>>n;
    string a,b,c,d;
    while(n--){
        cin>>a>>b>>c>>d;
        arr[0]={a.length(),'A'};
        arr[1]={b.length(),'B'};
        arr[2]={c.length(),'C'};
        arr[3]={d.length(),'D'};
        sort(arr,arr+4,[](pair<int, char> a,pair<int, char> b)-> bool {
            return a.first<b.first;
        });
        bool aa = arr[0].first<arr[1].first&&arr[0].first<arr[2].first&&arr[0].first<arr[3].first;
        bool ab = arr[0].first<arr[3].first&&arr[1].first<arr[3].first&&arr[2].first<arr[3].first;
        bool ac = arr[0].first==arr[1].first&&arr[2].first==arr[3].first&&arr[1].first==arr[2].first;
        if(aa&&!ab){
            cout<<arr[0].second<<"\n";
        }else if(ab&&!aa){
            cout<<arr[3].second<<"\n";
        }else cout<<"C\n";
    }
}