5308. 公路 - AcWing题库

#include <iostream>
#include <cstring>
#include <algorithm>
#include <queue>
#define endl '\n'
#define x first
#define y second

using namespace std;

typedef long long LL;
typedef pair<int,int> PII;

const int N = 100010;

int n,m;
LL ans,oil,dist;
int v[N],a[N];

void solve()
{
	cin >> n >> m;
	for (int i = 1;i < n;i ++) cin >> v[i];
	for (int i = 1;i <= n;i ++) cin >> a[i];
	
	int price = a[1];
	for (int i = 2;i <= n;i ++)
	{
		dist += v[i - 1];     //先更新距离
		LL t = (dist + m - 1) / m - oil;    //需要多少油
		ans += t * price;    //累加答案
		oil += t;    //更新现在有的油量
		price = min(price,a[i]);     // 更新最低油价
	}
	
	cout << ans << endl;
}

int main()
{
	ios::sync_with_stdio(0),cin.tie(0),cout.tie(0);
	int _ = 1;
	while(_--) solve();
	return 0;
}