#include <bits/stdc++.h>
using namespace std;
#define int long long
#define pii pair<int,int>
#define mii map<int,int>
#define F first
#define S second
#define pb push_back
#define fast ios_base::sync_with_stdio(false);cin.tie(0);cout.tie(0);
#pragma GCC optimize ("Ofast")
#pragma GCC optimize("unroll-loops")
#pragma GCC optimize ("-O2")
const int N = 1e5+5, mod = 1e9+7;
int h[N], w[N], ans[N], ps[N];
vector <int> v;
int inv2;
int pw(int a, int b)
{
if (b == 0)
return 1;
if (b % 2 == 1)
return ((pw(a * a % mod, b/2) % mod) * a) % mod;
return pw(a * a % mod, b/2) % mod;
}
int c2(int x)
{
x %= mod;
return (((x * (x-1)) % mod) * inv2) % mod;
}
int tr(int hr, int wr)
{
if (hr == 0 || wr == 0)
return 0;
int a;
a = c2(hr * wr) + (hr * c2(wr)) % mod + (wr * c2(hr)) % mod;
a = (a * inv2) % mod;
return (a + hr * wr)%mod;
}
int32_t main()
{
int n;
cin >> n;
inv2 = pw(2,mod-2);
for (int i = 1; i <= n; i++)
cin >> h[i];
for (int i = 1; i <= n; i++)
cin >> w[i], ps[i] = ps[i-1] + w[i];
h[0] = 0;
v.pb(0);
int sum = 0;
for (int i = 1; i <= n; i++)
{
while (h[v[v.size()-1]]>=h[i])
v.pop_back();
int j = v[v.size()-1];
v.pb(i);
int tw = ps[i] - ps[j];
ans[i] = (tr(tw,h[i]) - tr(tw-w[i],h[i])+mod);
ans[i] += (w[i]*ans[j])%mod;
ans[i] %= mod;
sum += ans[i];
sum %= mod;
}
cout << sum << endl;
}
# |
결과 |
실행 시간 |
메모리 |
Grader output |
1 |
Correct |
1 ms |
2396 KB |
Output is correct |
2 |
Incorrect |
1 ms |
2396 KB |
Output isn't correct |
3 |
Halted |
0 ms |
0 KB |
- |
# |
결과 |
실행 시간 |
메모리 |
Grader output |
1 |
Correct |
0 ms |
2396 KB |
Output is correct |
2 |
Correct |
1 ms |
2396 KB |
Output is correct |
3 |
Correct |
1 ms |
2396 KB |
Output is correct |
4 |
Correct |
0 ms |
2396 KB |
Output is correct |
5 |
Correct |
0 ms |
2396 KB |
Output is correct |
# |
결과 |
실행 시간 |
메모리 |
Grader output |
1 |
Correct |
1 ms |
2396 KB |
Output is correct |
2 |
Incorrect |
1 ms |
2396 KB |
Output isn't correct |
3 |
Halted |
0 ms |
0 KB |
- |
# |
결과 |
실행 시간 |
메모리 |
Grader output |
1 |
Incorrect |
1 ms |
2396 KB |
Output isn't correct |
2 |
Halted |
0 ms |
0 KB |
- |
# |
결과 |
실행 시간 |
메모리 |
Grader output |
1 |
Correct |
1 ms |
2396 KB |
Output is correct |
2 |
Incorrect |
1 ms |
2396 KB |
Output isn't correct |
3 |
Halted |
0 ms |
0 KB |
- |
# |
결과 |
실행 시간 |
메모리 |
Grader output |
1 |
Correct |
1 ms |
2392 KB |
Output is correct |
2 |
Incorrect |
1 ms |
2396 KB |
Output isn't correct |
3 |
Halted |
0 ms |
0 KB |
- |
# |
결과 |
실행 시간 |
메모리 |
Grader output |
1 |
Correct |
1 ms |
2396 KB |
Output is correct |
2 |
Incorrect |
1 ms |
2396 KB |
Output isn't correct |
3 |
Halted |
0 ms |
0 KB |
- |