题解

边输入边判断

#include <iostream>
using namespace std;
typedef long long ll;
int main(){
    int t;
    cin >> t;
    while(t--){
        int n;
        cin >> n;
        ll mx = 1e18;
        ll mn = 1e18;
        for(int i=1; i<=n; i++){
            int temp;
            cin >> temp;
            if(temp < mx){
                mn = mx;
                mx = temp;
            }
            else if(temp == mx){
                continue;
            }
            else if(temp < mn){
                mn = temp;
            }
        }
        if(mn != 1e18) cout << mn << endl;
        else cout << "NO" << endl;
    }
    return 0;
}