1041 Be Unique (20 分)

1041 Be Unique (20 分)

 

Being unique is so important to people on Mars that even their lottery is designed in a unique way. The rule of winning is simple: one bets on a number chosen from [1]. The first one who bets on a unique number wins. For example, if there are 7 people betting on { 5 31 5 88 67 88 17 }, then the second one who bets on 31 wins.

Input Specification:

Each input file contains one test case. Each case contains a line which begins with a positive integer N (≤) and then followed by N bets. The numbers are separated by a space.

Output Specification:

For each test case, print the winning number in a line. If there is no winner, print None instead.

Sample Input 1:

7 5 31 5 88 67 88 17

Sample Output 1:

31

Sample Input 2:

5 888 666 666 888 888

Sample Output 2:

None

应该没有比这更简单的题了
 

 

#include <bits/stdc++.h>

using namespace std;
int n;
int an[100005];
int vis[10005];
int main(){
    cin >> n;
    for(int i = 0; i<n; i++){
        cin >> an[i];
        vis[an[i]]++;
    }
    for(int i = 0; i < n; i++){
        if(vis[an[i]] == 1){
            cout << an[i] << endl;
            return 0;
        }
    }
    cout <<"None"<<endl;
    return 0;
}