暴力 70 正解 0 分/dk

#include <bits/stdc++.h>

using namespace std;

typedef long long ll;

const int MAXN = 1e5 + 10;

int n, k;

ll x, p, q;

int a[MAXN], ans;

ll sum, t, nxt;

int main() {
	scanf("%d%lld%lld%lld", &n, &x, &p, &q);
	for (int i = 1; i <= n; i++) scanf("%d", &a[i]); k = 1;
	while (1) {
		ans++, sum = 0;
		while (sum + a[k] < x && (t + x - sum - a[k]) * q >= p * ans * x && k <= n) sum += a[k], k++;
		if (k > n) break;
		t += x - sum;
		nxt = ((p - q) * x + q * (a[k] - t) + p * ans * x - 1) / ((q - p) * x) + 1;
		ans += nxt, t += nxt * x;
	}
	printf("%d", ans);
}