PAT 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, 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

/*  * 此题略水。 * 午睡操场传来蝉的声音 多少年后也还是很好听~~*/#include "iostream"#include "vector"#include "cstring"#include "string"#include "stack"#include "algorithm"using namespace std;int main() {int cnt[10001];int a[100001];int n;memset(cnt, 0, sizeof(cnt));cin >> n;for (int i = 0; i < n; i++) {int t;cin >> a[i];cnt[a[i]]++;}int i;for ( i = 0; i < n; i++)if (cnt[a[i]] == 1) {cout << a[i] << endl;break;}if (i == n)cout << "None" << endl;return 0;}