Submission #959874

#	Time	Username	Problem	Language	Result	Execution time	Memory
959874		penguin133	Fancy Fence (CEOI20_fancyfence)	C++17	25 / 100	19 ms	4700 KiB

fancyfence

#include <bits/stdc++.h>
using namespace std;
#define int long long
#define fi first
#define se second
#define pi pair <int, int> 
#define pii pair <int, pi>

int n, H[100005], W[100005], P[100005];
stack <pi> s;
int lst[105];
const int mod = 1e9 + 7;

void solve(){
	cin >> n;
	for(int i = 1; i <= n; i++)cin >> H[i];
	for(int i = 1; i <= n; i++)cin >> W[i];
	s.push({0, 0});
	int ans = 0;
	for(int i = 1; i <= n; i++){
		P[i] = P[i - 1] + W[i];
		P[i] %= mod;
		for(int j = H[i] + 1; j <= 100; j++)lst[j] = P[i];
		for(int j = 1; j <= H[i]; j++){
			ans += j * W[i] % mod * (P[i - 1] - lst[j] + mod) % mod;
			ans %= mod;
			int a = W[i] * (W[i] + 1) / 2;
			a %= mod;
			a *=j; a %= mod;
			ans += a; ans %= mod;
		}
		//cout << ans << '\n';
	}
	cout << ans;
}

main(){
	ios::sync_with_stdio(0);cin.tie(0);
	int tc = 1;
	//cin >> tc;
	while(tc--)solve();
}

Compilation message (stderr)

fancyfence.cpp:37:1: warning: ISO C++ forbids declaration of 'main' with no type [-Wreturn-type]
   37 | main(){
      | ^~~~

• Subtask 1: 0 / 0
• Subtask 2: 12 / 12
• Subtask 3: 13 / 13
• Subtask 4: 0 / 15
• Subtask 5: 0 / 15
• Subtask 6: 0 / 18
• Subtask 7: 0 / 27