1041 Be Unique (20)

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, 10^4^]. 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 (<=10^5^) 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


题目大意：给出一串数字，找出第一个不重复的数字；
思路：用一个数组记录每个数出现的次数， 用一个数组记录出现的数字

 1 #include<iostream>
 2 using namespace std;
 3 int main(){
 4   int n, temp; 
 5   cin>>n;
 6   int arr[10010], *t = new int[n];
 7   for(int i=0; i<n; i++){
 8     cin>>temp;
 9     arr[temp]++;
10     t[i] = temp;
11   }
12   bool flag = true;
13   for(int i=0; i<n; i++)
14     if(arr[t[i]]==1){ 
15       cout<<t[i]<<endl;
16       flag = false;
17       break;
18     }
19   if(flag) cout<<"None"<<endl;
20   return 0;
21 }