#include <bits/stdc++.h>
using namespace std;
#define fileio() freopen("input.txt", "r", stdin), freopen("output.txt", "w", stdout)
#define fastio() cin.tie(0), ios_base::sync_with_stdio(0)
#define pb push_back
#define endl "\n"
#define sp " "
#define pii pair<int, int>
#define st first
#define nd second
#define N 100005
#define L(node) node * 2
#define R(node) node * 2 + 1
#define int long long
const int INF = 1e9 + 7;
const int modulo = 1e9 + 7;
int h[N], w[N], pre[N];
pii tree[N * 4];
void build(int node, int l, int r)
{
if (l == r)
{
tree[node] = {h[l], l};
return;
}
int mid = (l + r) / 2;
build(L(node), l, mid);
build(R(node), mid + 1, r);
tree[node] = min(tree[L(node)], tree[R(node)]);
}
pii find(int node, int l, int r, int sl, int sr)
{
if (l > r || l > sr || r < sl) return {INF, INF};
if (l >= sl && r <= sr) return tree[node];
int mid = (l + r) / 2;
return min(find(L(node), l, mid, sl, sr), find(R(node), mid + 1, r, sl, sr));
}
int ans, n;
int add(int a, int b)
{
if (a + b < modulo) return a + b;
return a + b - modulo;
}
int mul(int a, int b)
{
return (a * b) % modulo;
}
int subs(int a, int b)
{
if (a < b) return a - b + modulo;
return a - b;
}
int fe(int a, int b)
{
if (b == 0) return 1;
if (b % 2) return mul(a, fe(a, b - 1));
int tmp = fe(a, b / 2);
return mul(tmp, tmp);
}
void f(int l, int r, int prev)
{
pii tmp = find(1, 1, n, l, r);
//cout<<l<<sp<<r<<sp<<tmp.st<<sp<<tmp.nd<<endl;
int maks = tmp.st;
int ind = tmp.nd;
int sum = subs(pre[r], pre[l - 1]);
int x = mul(sum, sum + 1);
//cout<<x<<sp;
x = mul(x, fe(2, modulo - 2));
//cout<<x<<sp;
x = mul(x, maks);
//cout<<x<<endl;
if (maks != prev) ans = add(ans, x);
if (ind > l) f(l, ind - 1, maks);
if (ind < r) f(ind + 1, r, maks);
}
int32_t main()
{
//fileio();
fastio();
cin>>n;
for (int i = 1; i <= n; i++)
cin>>h[i];
for (int j = 1; j <= n; j++)
{
cin>>w[j];
pre[j] = add(pre[j - 1], w[j]);
}
build(1, 1, n);
f(1, n, 0);
cout<<ans<<endl;
cerr<<"time taken : "<<(float)clock() / CLOCKS_PER_SEC<<" seconds\n";
}
# |
결과 |
실행 시간 |
메모리 |
Grader output |
1 |
Correct |
0 ms |
340 KB |
Output is correct |
2 |
Incorrect |
1 ms |
340 KB |
Output isn't correct |
3 |
Halted |
0 ms |
0 KB |
- |
# |
결과 |
실행 시간 |
메모리 |
Grader output |
1 |
Incorrect |
1 ms |
340 KB |
Output isn't correct |
2 |
Halted |
0 ms |
0 KB |
- |
# |
결과 |
실행 시간 |
메모리 |
Grader output |
1 |
Correct |
0 ms |
340 KB |
Output is correct |
2 |
Correct |
1 ms |
340 KB |
Output is correct |
3 |
Correct |
28 ms |
3572 KB |
Output is correct |
4 |
Correct |
56 ms |
6880 KB |
Output is correct |
5 |
Correct |
57 ms |
6764 KB |
Output is correct |
6 |
Correct |
55 ms |
6764 KB |
Output is correct |
# |
결과 |
실행 시간 |
메모리 |
Grader output |
1 |
Incorrect |
1 ms |
340 KB |
Output isn't correct |
2 |
Halted |
0 ms |
0 KB |
- |
# |
결과 |
실행 시간 |
메모리 |
Grader output |
1 |
Correct |
0 ms |
340 KB |
Output is correct |
2 |
Incorrect |
1 ms |
340 KB |
Output isn't correct |
3 |
Halted |
0 ms |
0 KB |
- |
# |
결과 |
실행 시간 |
메모리 |
Grader output |
1 |
Correct |
1 ms |
340 KB |
Output is correct |
2 |
Incorrect |
1 ms |
340 KB |
Output isn't correct |
3 |
Halted |
0 ms |
0 KB |
- |
# |
결과 |
실행 시간 |
메모리 |
Grader output |
1 |
Correct |
0 ms |
340 KB |
Output is correct |
2 |
Incorrect |
1 ms |
340 KB |
Output isn't correct |
3 |
Halted |
0 ms |
0 KB |
- |