WA了，没看出来哪错了，大佬救救我！

#include <bits/stdc++.h>

using namespace std;

int s[1005];

bool w = true;

int main() {
	int n, m;
	cin >> n >> m;
	for (int i = 1; i <= m; i++) {
		int t;
		cin >> t;
		s[t]--;
	}
	for (int i = 0; i < n; i++) {
		if (s[i] == 0) {
			cout << i << " "
			w = 0;
		}
	}
	if (w == 1) {
		cout << n << endl;
	}
	return 0;
}