public static int count(int[] a){
		int N = a.length;
		int count = 0;
		for(int i = 0; i < N; i++){
			for(int j = i+1; j < N; j++){
				for(int k = j+1; k < N; k++){
					if(a[i]+a[j]+a[k]==0)
						count++;
				}
			}
		}
		return count;
	}