【PAT】1041. Be Unique (20)

题目链接：http://pat.zju.edu.cn/contests/pat-a-practise/1041

题目描述：

 

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

 

分析：（1）直接用查询表。（2）有个坑爹的陷阱，用cin输入会超时，但是用scanf输入去可以通过。原因是？？？

参考代码：

 

#include<iostream>

#include<cstdio>

#include<string.h>

using namespace std;

int result[10000 + 5];

int input[100000 + 5];

int main()

{

	int n;

	cin>>n;

	int i;

	int temp;

	bool flag = false;



	for(i=0; i<n; i++)

	{

		//cin>>input[i];   用cin会超时, 用scanf不会

		scanf("%d",&input[i]);

		result[ input[i] ]++;

	}



	for(i=0; i<n; i++)

	{

		if(result[ input[i] ] == 1)

		{

			flag = true;

			break;

		}

	}

	if(flag)

		cout<<input[i]<<endl;

	

	else

		cout<<"None"<<endl;

	return 0;

}