点击链接PAT甲级-AC全解汇总

题目：
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 [1,10^​4​​ ]. 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 (≤10^​5​​ ) 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
1

Sample Output 1:

31
1

Sample Input 2:

5 888 666 666 888 888
1

Sample Output 2:

None
1

题意：

输入一堆数，返回第一个只出现了一次的数

我的代码：

#include
using namespace std;

int main()
{
    int N,nums[100100]={0},times[100100]={0};
    cin>>N;
    for(int i=0;i<N;i++)
    {
        cin>>nums[i];
        times[nums[i]]++;
    }
    for(int i=0;i<N;i++)
    {
        if(times[nums[i]]==1)
        {
            cout<<nums[i]<<endl;
            return 0;
        }
    }
    cout<<"None"<<endl;

    return 0;
}

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