【PAT】A1041. Be Unique (20)

Description:
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 (<=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

//NKW 甲级真题1030
#pragma warning(disable:4996)
#include <stdio.h>
#include <stdlib.h>
#include <string.h>
const int maxn = 10010, maxn1 = 100010;
int bet[maxn1], hash[maxn];
int main(){
	memset(hash, 0, sizeof(hash));
	int n;
	scanf("%d", &n);
	for (int i = 0; i < n; i++){
		scanf("%d", &bet[i]);
		hash[bet[i]]++;
	}
	int max = -1;
	for (int i = 0; i < n; i++){
		if (hash[bet[i]] == 1){
			max = bet[i];
			break;
		}
	}
	if (max != -1)
		printf("%d\n", max);
	else
		printf("None\n");
	system("pause");
	return 0;
}