为什么$n$，$q$ , $v$,等变量开int就会只对两个点，开long long之后就AC了

WA代码：

#include<bits/stdc++.h>
using namespace std;
const int maxn = 1e5 + 10;
long long a[maxn];
int n, q, v;
int main() {
	cin >> n >> q >> v;
	for (int i = 1; i <= n; i++)
		scanf("%lld", &a[i]);
	int x, y, ans = 0;
	for (int i = 1; i <= q; i++) {
		scanf("%lld%lld", &x, &y);
		a[x] = y;
	}
	for (int i = 1; i <= n; i++)
		if (a[i] >= v) ans++;
	cout << ans << endl;
	return 0;
}

AC就是把第5、10行int改成long long