Be Unique

问题 C: Be Unique (20)
时间限制: 1 Sec 内存限制: 32 MB
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.
输入
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.
输出
For each test case, print the winning number in a line. If there is no winner, print “None” instead.
样例输入
7 5 31 5 88 67 88 17
5 888 666 666 888 888
样例输出
31
None

#include<stdio.h>int main(){    int n;    while(scanf("%d",&n)!=EOF)    {        int flag=1,an[100005]={0},hash[10005]={0};        for(int i=0;i<n;i++)        {            scanf("%d",&an[i]);            hash[an[i]]++;        }        for(int i=0;i<n;i++)        {            if(hash[an[i]]==1)            {                flag=0;                printf("%d\n",an[i]);                break;            }        }        if(flag)        {            printf("None\n");        }    }    return 0;}