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 Nbets. 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
题意:关键句 "The first one who bets on a unique number wins" ,即找出第一个不重复出现的数字
代码
#include<iostream>
#include<cstdio>
#include<vector>
using namespace std;
const int Max=1e4+5;
int main()
{
int Bet[Max],N,x;
scanf("%d",&N);
vector<int> Mark;
for(int i=0;i<N;i++)
{
scanf("%d",&x);
if(!Bet[x])
Mark.push_back(x);
Bet[x]+=1;
}
for(int i=0;i<Mark.size();i++)
{
x=Mark[i];
if(Bet[x]==1)
{
printf("%d",x);
return 0;
}
}
printf("None");
return 0;
}