Problem:
Score : 300 points

Problem Statement

Given is a sequence of integers A_1, A_2, ..., A_N.
If its elements are pairwise distinct, print YES; otherwise, print NO.

Constraints

2 ≤ N ≤ 200000

1 ≤ A_i ≤ 10^9

All values in input are integers.

Input

Input is given from Standard Input in the following format:

N
A_1 ... A_N

Output

If the elements of the sequence are pairwise distinct, print YES; otherwise, print NO.

Sample Input 1

5
2 6 1 4 5

Sample Output 1

YES

The elements are pairwise distinct.

Sample Input 2

6
4 1 3 1 6 2

Sample Output 2

NO

The second and fourth elements are identical.

Sample Input 3

2
10000000 10000000

Sample Output 3

NO

Solution in C (GCC 5.4.1) (judge verdict: Wrong Answer)

#include <stdio.h>

int main() {
	int N, A[200000], i = 0;
	scanf("%d", &N);
	while (i < N) {
		scanf("%d", &A[i]);
		i++;
	}
	for (int s = 0; s < N;s++) {
		for (int t = s + 1; t < N; t++) {
			if (A[s]==A[t]) {
				goto L;
			}
		}
	}
	printf("Yes");
	goto M;
	L:printf("No");
	M:
	return 0;
}