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

 1 #include <stdio.h>  2 int lottery(int *,int); 3 int main(void) 4 { 5      //freopen("in.txt","r",stdin); 6      int n; 7      int num[100000]; 8      int i; 9      10      scanf("%d",&n);11      for(i=0;i<n;i++)12      {13           scanf("%d",&num[i]);14      }15      lottery(num,n);16      return 0;17 }18 int lottery (int *num,int n)19 {20      int i,j;21      int flag;22      int count[100000]={0};23      24      for(i=0;i<n;i++)25      {26           count[num[i]]++;27      }28      29      for(i=0;i<n;i++)30      {31           if(count[num[i]]==1)32                {33                     printf("%d\n",num[i]);34                     return 0;35                }36      }37           38      39      printf("None\n");40      return 0;41 }

1041. Be Unique (20)