#include <bits/stdc++.h>
#define int long long
#define fr first
#define sc second
#define pii pair<int,int>
using namespace std;
const int mod = 1e9 + 7;
int modpow(int a, int b){
if(b == 0) return 1;
int res = modpow(a, b / 2);
res = (res * res) % mod;
if(b & 1) res = (res * a) % mod;
return res;
}
int cal(int x){
return (x * (x + 1) / 2) % mod;
}
void solve(){
int n;
cin >> n;
vector<int> h(n + 1, 0), w(n + 1, 0);
for(int i = 1; i <= n; ++i) cin >> h[i];
for(int i = 1; i <= n; ++i) cin >> w[i];
stack<int> stk;
stk.push(0);
int ans = 0;
vector<int> dp(n + 1, 0), pre(n + 1, 0);
for(int i = 1; i <= n; ++i) pre[i] = pre[i-1] + w[i];
for(int i = 1; i <= n; ++i) {
while (h[stk.top()] >= h[i]) stk.pop();
dp[i] = dp[stk.top()] + cal(h[i]) * (pre[i] - pre[stk.top()]);
ans = (ans + dp[stk.top()] * w[i]) % mod;
ans = (ans + cal(h[i]) * (pre[i - 1] - pre[stk.top()]) * w[i]) % mod;
ans = (ans + cal(h[i]) * cal(w[i])) % mod;
stk.push(i);
}
cout << ans << endl;
}
signed main(){
ios::sync_with_stdio(0);
cin.tie(0);
//freopen("bbreeds.in", "r");
//freopen("bbreeds.out", "w");
solve();
}
# |
Verdict |
Execution time |
Memory |
Grader output |
1 |
Correct |
0 ms |
204 KB |
Output is correct |
2 |
Incorrect |
1 ms |
332 KB |
Output isn't correct |
# |
Verdict |
Execution time |
Memory |
Grader output |
1 |
Correct |
0 ms |
204 KB |
Output is correct |
2 |
Correct |
0 ms |
204 KB |
Output is correct |
3 |
Correct |
0 ms |
204 KB |
Output is correct |
4 |
Correct |
0 ms |
204 KB |
Output is correct |
5 |
Correct |
0 ms |
204 KB |
Output is correct |
# |
Verdict |
Execution time |
Memory |
Grader output |
1 |
Correct |
0 ms |
204 KB |
Output is correct |
2 |
Incorrect |
1 ms |
332 KB |
Output isn't correct |
3 |
Halted |
0 ms |
0 KB |
- |
# |
Verdict |
Execution time |
Memory |
Grader output |
1 |
Incorrect |
1 ms |
332 KB |
Output isn't correct |
2 |
Halted |
0 ms |
0 KB |
- |
# |
Verdict |
Execution time |
Memory |
Grader output |
1 |
Correct |
0 ms |
204 KB |
Output is correct |
2 |
Incorrect |
1 ms |
332 KB |
Output isn't correct |
3 |
Halted |
0 ms |
0 KB |
- |
# |
Verdict |
Execution time |
Memory |
Grader output |
1 |
Correct |
0 ms |
204 KB |
Output is correct |
2 |
Incorrect |
1 ms |
332 KB |
Output isn't correct |
3 |
Halted |
0 ms |
0 KB |
- |
# |
Verdict |
Execution time |
Memory |
Grader output |
1 |
Correct |
0 ms |
204 KB |
Output is correct |
2 |
Incorrect |
1 ms |
332 KB |
Output isn't correct |