有两个结果RE了，为什么啊？

#include <iostream>
using namespace std;
int n,m,k,cnt;
int arr[120][120];
int main() {
	cin >> n >> m >> k;
	for (int p = 1; p <= m; p++) {
		int i = 0, j = 0;
		cin >> i >> j;
		arr[i][j] = arr[i - 2][j] = arr[i - 1][j] = arr[i - 1][j - 1] = arr[i - 1][j + 1] = arr[i][j - 2] = arr[i][j - 1] = arr[i][j + 1] = arr[i][j + 2] = arr[i + 1][j - 1] = arr[i + 1][j] = arr[i + 1][j + 1] = arr[i + 2][j] = 1;
	}
	for (int p = 1; p <= k; p++) {
		int a = 0, s = 0;
		cin >> a >> s;
		for (int o = a - 2; o <= a + 2; o++) {
			for (int u = s - 2; u <= s + 2; u++) {
				arr[o][u] = 1;
			}
		}
	}
	for (int x = 1; x <= n; x++) {
		for (int y = 1; y <= n; y++) {
			if (arr[x][y] == 0) {
				cnt++;
			}
		}
	}
	cout << cnt << endl;
	return 0;
}