#include <bits/stdc++.h>
using namespace std;
const int MOD = 1e9 + 7;
const int TWOINV = 5e8 + 4;
const int MAXN = 1e5 + 25;
int add (int a, int b) {
a += b; if (a >= MOD) a -= MOD;
return a;
}
int sub (int a, int b) {
a -= b; if (a < 0) a += MOD;
return a;
}
int mul (int a, int b) {
return (a * 1ll * b) % MOD;
}
int h[MAXN], w[MAXN], n;
int nxt[MAXN], prv[MAXN], sze[MAXN];
vector <int> adj[MAXN];
bool comp (int x, int y) {
return h[x] == h[y] ? x < y : h[x] < h[y];
}
int ans;
void dfs (int pos) {
sze[pos] = w[pos];
int x = mul(h[pos], mul(h[pos] + 1, TWOINV));
for (auto j : adj[pos]) {
dfs(j);
ans = add(ans, mul(sze[j], mul(sze[pos], x)));
sze[pos] = add(sze[pos], sze[j]);
}
}
int main () {
ios::sync_with_stdio(0); cin.tie(0);
cin >> n; memset(nxt, -1, sizeof(nxt)); memset(prv, -1, sizeof(prv));
for (int i = 1; i <= n; i++) cin >> h[i];
for (int i = 1; i <= n; i++) cin >> w[i];
for (int i = 1; i <= n; i++) {
int x = w[i], y = h[i];
x = mul(x, mul(x + 1, TWOINV));
y = mul(y, mul(y + 1, TWOINV));
ans = add(ans, mul(x, y));
}
stack <int> cur;
for (int i = 1; i <= n; i++) {
while (!cur.empty() && comp(i, cur.top())) {
nxt[cur.top()] = i;
cur.pop();
}
cur.push(i);
}
while (!cur.empty()) cur.pop();
for (int i = n; i >= 1; i--) {
while (!cur.empty() && comp(i, cur.top())) {
prv[cur.top()] = i;
cur.pop();
}
cur.push(i);
}
while (!cur.empty()) cur.pop();
int root = -1;
for (int i = 1; i <= n; i++) {
if (nxt[i] == -1 && prv[i] == -1) {
root = i;
continue;
}
if (nxt[i] == -1) {
adj[prv[i]].push_back(i);
} else if (prv[i] == -1) {
adj[nxt[i]].push_back(i);
} else if (!comp(nxt[i], prv[i])) {
adj[nxt[i]].push_back(i);
} else {
adj[prv[i]].push_back(i);
}
}
dfs(root);
cout << ans << '\n';
}
# |
결과 |
실행 시간 |
메모리 |
Grader output |
1 |
Correct |
1 ms |
4700 KB |
Output is correct |
2 |
Correct |
2 ms |
4700 KB |
Output is correct |
# |
결과 |
실행 시간 |
메모리 |
Grader output |
1 |
Correct |
1 ms |
4700 KB |
Output is correct |
2 |
Correct |
2 ms |
4700 KB |
Output is correct |
3 |
Correct |
1 ms |
4696 KB |
Output is correct |
4 |
Correct |
1 ms |
4700 KB |
Output is correct |
5 |
Correct |
2 ms |
4700 KB |
Output is correct |
# |
결과 |
실행 시간 |
메모리 |
Grader output |
1 |
Correct |
1 ms |
4700 KB |
Output is correct |
2 |
Correct |
1 ms |
4700 KB |
Output is correct |
3 |
Correct |
11 ms |
7516 KB |
Output is correct |
4 |
Correct |
22 ms |
14676 KB |
Output is correct |
5 |
Correct |
22 ms |
11344 KB |
Output is correct |
6 |
Correct |
20 ms |
9308 KB |
Output is correct |
# |
결과 |
실행 시간 |
메모리 |
Grader output |
1 |
Correct |
2 ms |
4696 KB |
Output is correct |
2 |
Correct |
3 ms |
5724 KB |
Output is correct |
3 |
Correct |
14 ms |
11004 KB |
Output is correct |
4 |
Correct |
27 ms |
17620 KB |
Output is correct |
5 |
Correct |
31 ms |
17748 KB |
Output is correct |
6 |
Correct |
1 ms |
4696 KB |
Output is correct |
# |
결과 |
실행 시간 |
메모리 |
Grader output |
1 |
Correct |
1 ms |
4700 KB |
Output is correct |
2 |
Correct |
2 ms |
4700 KB |
Output is correct |
3 |
Correct |
4 ms |
5724 KB |
Output is correct |
4 |
Correct |
15 ms |
11100 KB |
Output is correct |
5 |
Correct |
27 ms |
17484 KB |
Output is correct |
6 |
Correct |
30 ms |
17664 KB |
Output is correct |
7 |
Correct |
1 ms |
4696 KB |
Output is correct |
8 |
Correct |
3 ms |
5980 KB |
Output is correct |
9 |
Correct |
14 ms |
11100 KB |
Output is correct |
10 |
Correct |
26 ms |
17492 KB |
Output is correct |
11 |
Correct |
27 ms |
17500 KB |
Output is correct |
12 |
Correct |
1 ms |
4700 KB |
Output is correct |
# |
결과 |
실행 시간 |
메모리 |
Grader output |
1 |
Correct |
1 ms |
4700 KB |
Output is correct |
2 |
Correct |
1 ms |
4700 KB |
Output is correct |
3 |
Correct |
1 ms |
4700 KB |
Output is correct |
4 |
Correct |
1 ms |
4700 KB |
Output is correct |
5 |
Correct |
1 ms |
4700 KB |
Output is correct |
6 |
Correct |
1 ms |
4700 KB |
Output is correct |
7 |
Correct |
1 ms |
4700 KB |
Output is correct |
8 |
Correct |
2 ms |
4700 KB |
Output is correct |
9 |
Correct |
1 ms |
4700 KB |
Output is correct |
10 |
Correct |
1 ms |
4700 KB |
Output is correct |
11 |
Correct |
1 ms |
4700 KB |
Output is correct |
12 |
Correct |
2 ms |
4952 KB |
Output is correct |
13 |
Correct |
1 ms |
4700 KB |
Output is correct |
14 |
Correct |
1 ms |
4700 KB |
Output is correct |
15 |
Correct |
1 ms |
4700 KB |
Output is correct |
16 |
Correct |
1 ms |
4700 KB |
Output is correct |
# |
결과 |
실행 시간 |
메모리 |
Grader output |
1 |
Correct |
1 ms |
4700 KB |
Output is correct |
2 |
Correct |
2 ms |
4700 KB |
Output is correct |
3 |
Correct |
1 ms |
4696 KB |
Output is correct |
4 |
Correct |
2 ms |
4700 KB |
Output is correct |
5 |
Correct |
1 ms |
4700 KB |
Output is correct |
6 |
Correct |
1 ms |
4700 KB |
Output is correct |
7 |
Correct |
1 ms |
4700 KB |
Output is correct |
8 |
Correct |
1 ms |
4700 KB |
Output is correct |
9 |
Correct |
1 ms |
4700 KB |
Output is correct |
10 |
Correct |
1 ms |
4700 KB |
Output is correct |
11 |
Correct |
12 ms |
7516 KB |
Output is correct |
12 |
Correct |
23 ms |
14684 KB |
Output is correct |
13 |
Correct |
22 ms |
11356 KB |
Output is correct |
14 |
Correct |
20 ms |
9300 KB |
Output is correct |
15 |
Correct |
2 ms |
4696 KB |
Output is correct |
16 |
Correct |
4 ms |
5980 KB |
Output is correct |
17 |
Correct |
14 ms |
11100 KB |
Output is correct |
18 |
Correct |
32 ms |
17520 KB |
Output is correct |
19 |
Correct |
28 ms |
17744 KB |
Output is correct |
20 |
Correct |
1 ms |
4696 KB |
Output is correct |
21 |
Correct |
4 ms |
5980 KB |
Output is correct |
22 |
Correct |
14 ms |
11100 KB |
Output is correct |
23 |
Correct |
26 ms |
17488 KB |
Output is correct |
24 |
Correct |
27 ms |
17572 KB |
Output is correct |
25 |
Correct |
2 ms |
4696 KB |
Output is correct |
26 |
Correct |
2 ms |
4700 KB |
Output is correct |
27 |
Correct |
1 ms |
4700 KB |
Output is correct |
28 |
Correct |
2 ms |
4700 KB |
Output is correct |
29 |
Correct |
2 ms |
4696 KB |
Output is correct |
30 |
Correct |
4 ms |
4952 KB |
Output is correct |
31 |
Correct |
4 ms |
4956 KB |
Output is correct |
32 |
Correct |
13 ms |
6492 KB |
Output is correct |
33 |
Correct |
13 ms |
6656 KB |
Output is correct |
34 |
Correct |
24 ms |
8540 KB |
Output is correct |
35 |
Correct |
24 ms |
8528 KB |
Output is correct |
36 |
Correct |
29 ms |
8572 KB |
Output is correct |
37 |
Correct |
25 ms |
8568 KB |
Output is correct |
38 |
Correct |
1 ms |
4696 KB |
Output is correct |
39 |
Correct |
24 ms |
9492 KB |
Output is correct |
40 |
Correct |
23 ms |
9820 KB |
Output is correct |
41 |
Correct |
23 ms |
11400 KB |
Output is correct |
42 |
Correct |
27 ms |
17488 KB |
Output is correct |