PAT-PAT (Advanced Level) PractiseBe Unique (20) 【一星级】

题目链接：http://www.patest.cn/contests/pat-a-practise/1041

题面：

1041. Be Unique (20)

时间限制

100 ms

内存限制

65536 kB

代码长度限制

16000 B

判题程序

Standard

作者

CHEN, Yue

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, 10⁴]. 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 (<=10⁵) 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

题目大意：

给定一数列，求出其中第一个仅出现一次的数，没有则输出"None"。

代码：

#include <iostream>
#include <cstdio>
#include <algorithm>
#include <queue>
#include <cstring>
using namespace std;
int cnt[10010],ori[100010];
int main()
{
    int n;
    cin>>n;
    bool flag=true;
    memset(cnt,0,sizeof(cnt));
    for(int i=1;i<=n;i++)
    {
    	cin>>ori[i];
    	cnt[ori[i]]++;
    }
    for(int i=1;i<=n;i++)
    {
    	if(cnt[ori[i]]==1)
  	    {
    	   cout<<ori[i]<<endl;
    	   flag=false;
		   break;  	
  	    }
    }
    if(flag)cout<<"None\n"; 
	return 0;
}