Be Unique

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 [1,104]. 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.
  • 时间限制: 400 ms
  • 内存限制: 64 MB
  • 代码长度限制: 16 KB

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

我的作答 编译器：C++(g++)

#include <iostream>
using namespace std;

int main()
{
    int N, i;
	short number[100000], tag[10000];
    cin >> N;
    for(i = 0; i < N; ++i)
    {
    	cin >> number[i];
    	switch(tag[number[i]])
    	{
    		case -1:
				break;
			case 0:
				tag[number[i]] = 1;
				break;
			case 1:
				tag[number[i]] = -1;
				break;
		}
	}
	
	for(i = 0; i < N; ++i)
	{
		if(tag[number[i]] == 1)
		{
			cout << number[i];
			return 0;
		}
	}
	cout << "None";
	return 0;
}