1041 Be Unique (20 分)
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
using namespace std;
#include<algorithm>
#include<iostream>
#include<cstdio>
#include<cstring>
int num[10010] = {0};//每个数字出现的次数
int bet[100010] = {0};//每个人赌出的数字
int main()
{
int N = 0;
scanf("%d", &N);
for(int i=0; i<N; i++)
{
scanf("%d", &bet[i]);
num[bet[i]]++;//该数字出现次数累计
}
int flag = 0;//已经出现则置一,没有满足题意的则输出None
for(int i=0; i<N; i++)
{
if(num[bet[i]] == 1)//首次赌出的唯一数字
{
flag = 1;
printf("%d", bet[i]);
break;
}
}
if(!flag) printf("None");
return 0;
}