1041. Be Unique (20)

注意n的值很大的时候不能使用两层嵌套算法，这样执行时间将会很长

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

来源： <http://www.patest.cn/contests/pat-a-practise/1041>

#pragma warning(disable:4996)
#include <stdio.h>

using namespace std;

int main(void) {
	int n = 0;
	int num[100001] = { 0 };
	int num2[100001] = { 0 };
	int i = 0, j = 0;
	int flag = 0,count=0;
	int temp = 0;

	scanf("%d", &n);
	for (i = 0; i < n; i++) {
		scanf("%d", &temp);
		num[i] = temp;
		num2[temp]++;
	}
	
	for (i = 0; i < n; i++) {
		if (num2[num[i]] == 1) {
			printf("%d", num[i]);
			flag = 1;
			break;
		}
	}

	if(flag==0)
		printf("None");

	
	
	return 0;


}

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