// Only GOD
// believe in yourself
#include <bits/stdc++.h>
using namespace std;
typedef long long ll;
typedef long double ld;
typedef pair<int, int> pii;
#define F first
#define S second
#define pb push_back
#define all(x) x.begin(), x.end()
#define bit(x, y) ((x >> y)&1)
#define sz(x) (int)x.size()
#define kill(x) return cout << x << '\n', void()
#define KILL(x) return cout << x << '\n', 0
#define int ll
const int N = 1e5+10;
const int INF = 1e9+10;
const int MOD = 1e9+7;
int mul(int a, int b){
a %= MOD;
b %= MOD;
return (a*b)%MOD;
}
int add(int a, int b){
return (a+b+MOD)%MOD;
}
int dp[N], h[N], w[N], ps[N], psw[N];
int inv;
int f(int n){
return mul(mul(n, n+1)%MOD, inv)%MOD;
}
int pw(int a, int b){
int res = 1;
while(b){
if(b & 1)
res = mul(a, res);
a = mul(a, a);
b >>= 1;
}
return res;
}
int node[N << 1];
void upd(int x, int p){
p += N;
node[p] = x;
p >>= 1;
for(; p; p >>= 1)
node[p] = min(node[p*2], node[p*2+1]);
}
int get(int l, int r){
int mn = INF;
l += N, r += N;
while(l < r){
if(l&1)
mn = min(node[l++], mn);
if(r & 1)
mn = min(node[--r], mn);
l >>= 1;
r >>= 1;
}
return mn;
}
int get2(int l, int r, int val){
if(get(l, r) >= val)
return -1;
while(r - l > 1){
int mid = (l+r)>>1;
if(get(mid, r) < val)
l = mid;
else
r = mid;
}
return l;
}
int32_t main(){
ios::sync_with_stdio(0);cin.tie(0);cout.tie(0);
for(int i = 0; i < 2*N; i++)
node[i] = INF;
int n;
cin >> n;
inv = pw(2, MOD-2);
for(int i = 1; i <= n; i++){
cin >> h[i];
upd(h[i], i);
}
for(int i = 1; i <= n;i++){
cin >> w[i];
psw[i] = psw[i-1]+w[i];
}
int ans=0;
for(int i = 1; i <= n; i++){
dp[i] = mul(w[i], f(h[i]));
dp[i] = add(dp[i], mul(f(w[i]-1), f(h[i])));
if(h[i] < h[i-1]){
int j = get2(1, i, h[i]);
if(j==-1){
ps[i-1] = mul(psw[i-1], f(h[i]));
}
else{
ps[i-1] = add(ps[j], mul(psw[i-1] - psw[j-1], f(h[i])));
}
}
ps[i] = add(mul(w[i], f(h[i])),ps[i-1]);
int res =0;
res = ps[i-1];
dp[i] = add(dp[i], mul(res, w[i]));
ans = add(ans, dp[i]);
}
KILL(ans);
}
# |
Verdict |
Execution time |
Memory |
Grader output |
1 |
Correct |
1 ms |
1876 KB |
Output is correct |
2 |
Incorrect |
1 ms |
1876 KB |
Output isn't correct |
3 |
Halted |
0 ms |
0 KB |
- |
# |
Verdict |
Execution time |
Memory |
Grader output |
1 |
Incorrect |
1 ms |
1876 KB |
Output isn't correct |
2 |
Halted |
0 ms |
0 KB |
- |
# |
Verdict |
Execution time |
Memory |
Grader output |
1 |
Correct |
1 ms |
1876 KB |
Output is correct |
2 |
Correct |
2 ms |
1876 KB |
Output is correct |
3 |
Correct |
14 ms |
3816 KB |
Output is correct |
4 |
Correct |
25 ms |
5704 KB |
Output is correct |
5 |
Correct |
26 ms |
5792 KB |
Output is correct |
6 |
Correct |
23 ms |
5784 KB |
Output is correct |
# |
Verdict |
Execution time |
Memory |
Grader output |
1 |
Correct |
1 ms |
1876 KB |
Output is correct |
2 |
Correct |
4 ms |
2260 KB |
Output is correct |
3 |
Correct |
14 ms |
3852 KB |
Output is correct |
4 |
Correct |
27 ms |
5780 KB |
Output is correct |
5 |
Correct |
38 ms |
5696 KB |
Output is correct |
6 |
Correct |
1 ms |
1876 KB |
Output is correct |
# |
Verdict |
Execution time |
Memory |
Grader output |
1 |
Correct |
1 ms |
1876 KB |
Output is correct |
2 |
Correct |
1 ms |
1876 KB |
Output is correct |
3 |
Correct |
4 ms |
2260 KB |
Output is correct |
4 |
Correct |
16 ms |
3816 KB |
Output is correct |
5 |
Correct |
27 ms |
5728 KB |
Output is correct |
6 |
Correct |
29 ms |
5676 KB |
Output is correct |
7 |
Correct |
1 ms |
1876 KB |
Output is correct |
8 |
Correct |
4 ms |
2260 KB |
Output is correct |
9 |
Correct |
15 ms |
3796 KB |
Output is correct |
10 |
Correct |
26 ms |
5732 KB |
Output is correct |
11 |
Correct |
27 ms |
5772 KB |
Output is correct |
12 |
Correct |
1 ms |
1876 KB |
Output is correct |
# |
Verdict |
Execution time |
Memory |
Grader output |
1 |
Correct |
1 ms |
1876 KB |
Output is correct |
2 |
Incorrect |
1 ms |
1876 KB |
Output isn't correct |
3 |
Halted |
0 ms |
0 KB |
- |
# |
Verdict |
Execution time |
Memory |
Grader output |
1 |
Correct |
1 ms |
1876 KB |
Output is correct |
2 |
Incorrect |
1 ms |
1876 KB |
Output isn't correct |
3 |
Halted |
0 ms |
0 KB |
- |