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]. 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 (<=10) 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
#include <iostream>
#include <set>
using namespace std; int main(){
int n;
int i,t;
cin>>n;
set<int> s,s1;
int record[n];
cin>>t;
s.insert(t);
s1.insert(t);
record[] = t;
for(i = ; i < n; i++){
cin>>t;
record[i] = t;
if(s1.find(t) != s1.end() && s.find(t) != s.end()){
s.erase(t);
}
else if(s1.find(t) == s1.end()){
s.insert(t);
s1.insert(t);
} }
if(s.empty()){
cout<<"None";
}else{
i = ;
while(s.find(record[i]) == s.end()){
i++;
}
cout<<record[i]<<endl;
}
return ;
}