1041 Be Unique (20分)(水)
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]. 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 (≤) 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
![](https://images.cnblogs.com/OutliningIndicators/ContractedBlock.gif)
1 #define _CRT_SECURE_NO_WARNINGS 2 #include <climits> 3 #include<iostream> 4 #include<vector> 5 #include<queue> 6 #include<map> 7 #include<set> 8 #include<stack> 9 #include<algorithm> 10 #include<string> 11 #include<cmath> 12 using namespace std; 13 int num[10000]; 14 int main() 15 { 16 int N; 17 cin >> N; 18 vector<int> V(N); 19 int n = -1; 20 for (int i = 0; i < N; i++) 21 { 22 cin >> V[i]; 23 num[V[i]]++; 24 } 25 for (int i = 0; i < N; i++) 26 { 27 if (num[V[i]] == 1) 28 { 29 n = i; 30 break; 31 } 32 } 33 if (n != -1) 34 cout << V[n]; 35 else 36 cout << "None"; 37 }