#include <bits/stdc++.h>
using namespace std;
// ordered set whith s.order_of_key(x) method, which returns rank of element x in set s
/*
#include <ext/pb_ds/assoc_container.hpp>
#include <ext/pb_ds/tree_policy.hpp>
using namespace __gnu_pbds;
typedef tree<int, null_type, less_equal<int>, rb_tree_tag, tree_order_statistics_node_update> ordered_set;
*/
// pair printing
template <class T, class U>
ostream& operator<<(ostream& out, const pair<T, U> &par) {out << "(" << par.first << "; " << par.second << ")"; return out;}
// set printing
template <class T>
ostream& operator<<(ostream& out, const set<T> &cont) { out << "{"; for(const auto &x:cont) out << x << ", "; out << "}"; return out; }
// map printing
template <class T, class U>
ostream& operator<<(ostream& out, const map<T, U> &cont) {out << "{"; for(const auto &x:cont) out << x << ", "; out << "}"; return out; }
// unordered_set printing
template <class T>
ostream& operator<<(ostream& out, const unordered_set<T> &cont) {out << "{";for(const auto &x:cont) out << x << ", ";out << "}";return out;}
// unordered_map printing
template <class T, class U>
ostream& operator<<(ostream& out, const unordered_map<T, U> &cont) {out << "{";for(const auto &x:cont) out << x << ", ";out << "}";return out;}
// vector printing
template<class T>
ostream& operator<<(ostream& out, const vector<T> &cont){ out << "["; for (const auto &x:cont) out << x << ", "; out << "]"; return out;}
#define print(x) cout << (x) << endl;
#define dmp(x) cerr << #x << " = " << x << endl
#define dmpn(x) cerr << #x << " = " << x << "; "
#define dmpl(x) cerr << "Line " << __LINE__ << ": " << #x << " = " << x << endl
#define int long long
using ll = long long;
using ld = long double;
using pii = pair<int, int>;
using pll = pair<ll, ll>;
#define pb push_back
#define ff first
#define ss second
#define all(x) begin(x), end(x)
#define sz(x) (int)x.size()
#define contains(s,x) ((s).find(x) != (s).end())
const int MOD = 1e9 + 7;
int fast_pow(int a, int b) {
int ans = 1;
while (b > 0) {
if (b % 2 == 1) ans = ((ll)a * (ll)ans) % MOD;
a = ((ll)a * (ll)a) % MOD;
b /= 2;
}
return ans;
}
int divide(int a, int b) {
return ((ll)a * (ll)fast_pow(b, MOD - 2)) % MOD;
}
int rect_cnt(int h, int w) {
int a = (h * w) % MOD;
int b = divide((a * ((w - 1) + (h - 1))) % MOD, 2);
int c = divide(((a * ((h - 1) * (w - 1))) % MOD) % MOD, 4);
return (a + b + c) % MOD;
}
void solve() {
int N;
cin >> N;
vector<int> hs(N), ws(N), p(N + 1, 0);
for (int i = 0; i < N; i++) cin >> hs[i];
for (int i = 0; i < N; i++) cin >> ws[i];
for (int i = 0; i < N; i++) p[i + 1] = p[i] + ws[i];
// dmp(rect_cnt(3, 1));
int ans = 0;
vector<pii> stck;
for (int i = 0; i < N; i++) {
while (!stck.empty() && hs[stck.back().ff] > hs[i]) stck.pop_back();
int h = hs[i], w = ws[i];
int new_ending = (rect_cnt(h, 1) * w) % MOD;
if (stck.empty()) {
stck.pb({ i, new_ending });
ans = (ans + new_ending) % MOD;
}
int last_h = hs[stck.back().ff];
int last_pos = p[stck.back().ff + 1];
int inter_ending = (rect_cnt(last_h, 1) * (p[i] - last_pos)) % MOD;
ans = (ans + stck.back().ss + inter_ending + rect_cnt(h, w)) % MOD;
stck.pb({ i, stck.back().ss + inter_ending + new_ending });
}
cout << ans << endl;
}
int32_t main() {
ios::sync_with_stdio(false);
cin.tie(0);
cout.tie(0);
int t = 1;
// cin >> t;
while (t--) {
solve();
}
}
| # |
Verdict |
Execution time |
Memory |
Grader output |
| 1 |
Correct |
1 ms |
212 KB |
Output is correct |
| 2 |
Incorrect |
1 ms |
340 KB |
Output isn't correct |
| 3 |
Halted |
0 ms |
0 KB |
- |
| # |
Verdict |
Execution time |
Memory |
Grader output |
| 1 |
Incorrect |
1 ms |
212 KB |
Output isn't correct |
| 2 |
Halted |
0 ms |
0 KB |
- |
| # |
Verdict |
Execution time |
Memory |
Grader output |
| 1 |
Correct |
1 ms |
320 KB |
Output is correct |
| 2 |
Incorrect |
2 ms |
340 KB |
Output isn't correct |
| 3 |
Halted |
0 ms |
0 KB |
- |
| # |
Verdict |
Execution time |
Memory |
Grader output |
| 1 |
Incorrect |
1 ms |
340 KB |
Output isn't correct |
| 2 |
Halted |
0 ms |
0 KB |
- |
| # |
Verdict |
Execution time |
Memory |
Grader output |
| 1 |
Correct |
1 ms |
212 KB |
Output is correct |
| 2 |
Incorrect |
1 ms |
340 KB |
Output isn't correct |
| 3 |
Halted |
0 ms |
0 KB |
- |
| # |
Verdict |
Execution time |
Memory |
Grader output |
| 1 |
Correct |
1 ms |
256 KB |
Output is correct |
| 2 |
Incorrect |
1 ms |
340 KB |
Output isn't correct |
| 3 |
Halted |
0 ms |
0 KB |
- |
| # |
Verdict |
Execution time |
Memory |
Grader output |
| 1 |
Correct |
1 ms |
212 KB |
Output is correct |
| 2 |
Incorrect |
1 ms |
340 KB |
Output isn't correct |
| 3 |
Halted |
0 ms |
0 KB |
- |
