#include <bits/stdc++.h>
using namespace std;
#ifdef evenvalue
#include "debug.h"
#define debug(...) print(#__VA_ARGS__, __VA_ARGS__)
#else
#define debug(...)
#endif
using int64 = long long;
using ld = long double;
template<typename T>
using min_heap = priority_queue<T, vector<T>, greater<T>>;
template<typename T>
using max_heap = priority_queue<T, vector<T>, less<T>>;
namespace read {
int Int() {
int x;
cin >> x;
return x;
}
int64 Int64() {
int64 x;
cin >> x;
return x;
}
char Char() {
char c;
cin >> c;
return c;
}
string String() {
string s;
cin >> s;
return s;
}
double Double() {
return stod(String());
}
ld LongDouble() {
return stold(String());
}
template<typename T1, typename T2>
pair<T1, T2> Pair() {
pair<T1, T2> p;
cin >> p.first >> p.second;
return p;
}
template<typename T>
vector<T> Vec(const int n) {
vector<T> v(n);
for (T &x : v) {
cin >> x;
}
return v;
}
template<typename T>
vector<vector<T>> VecVec(const int n, const int m) {
vector<vector<T>> v(n);
for (vector<T> &vec : v) {
vec = Vec<T>(m);
}
return v;
}
}//namespace read
constexpr int kInf = 1e9 + 10;
constexpr int64 kInf64 = 1e15 + 10;
constexpr int kMod = 1e9 + 7;
constexpr int kMaxN = 2e5 + 10;
struct section {
int h;
int w;
};
const section point = {0, 0};
int nC2(const int x) {
return (x * 1LL * (x - 1) / 2) % kMod;
}
int fancy(const section s) {
const int h = nC2(s.h + 1);
const int w = nC2(s.w + 1);
return (h * 1LL * w) % kMod;
}
int fancy(vector<section> a) {
const int n = a.size();
a.insert(a.begin(), point);
vector<int> w_sum(n + 1);
w_sum.back() = a.back().w;
for (int i = n - 1; i >= 0; i--) {
w_sum[i] = w_sum[i + 1] + a[i].w;
}
int ans = 0;
for (int i = 1; i <= n; i++) {
ans += fancy({a[i].h, w_sum[i]}) - fancy({a[i - 1].h, w_sum[i]});
ans += (ans < 0 ? kMod : 0);
ans -= (ans >= kMod ? kMod : 0);
}
return ans;
}
inline void solution() {
const int n = read::Int();
vector<section> a(n);
for (int i = 0; i < n; i++) {
a[i].h = read::Int();
}
for (int i = 0; i < n; i++) {
a[i].w = read::Int();
}
a.push_back(point);
int ans = 0;
vector<section> stk = {point};
for (section s : a) {
vector<section> rem;
while (not stk.empty() and stk.back().h >= s.h) {
rem.push_back(stk.back());
s.w += stk.back().w;
stk.pop_back();
}
stk.push_back(s);
reverse(rem.begin(), rem.end());
ans += fancy(rem);
ans -= (ans >= kMod ? kMod : 0);
}
cout << ans << '\n';
}
int32_t main() {
ios_base::sync_with_stdio(false);
cin.tie(nullptr);
//freopen(".in", "r", stdin);
//freopen(".out", "w", stdout);
cout << fixed << setprecision(10);
int testcases = 1;
//cin >> testcases;
while (testcases--) {
solution();
}
}
# |
Verdict |
Execution time |
Memory |
Grader output |
1 |
Correct |
1 ms |
344 KB |
Output is correct |
2 |
Incorrect |
1 ms |
344 KB |
Output isn't correct |
3 |
Halted |
0 ms |
0 KB |
- |
# |
Verdict |
Execution time |
Memory |
Grader output |
1 |
Incorrect |
0 ms |
600 KB |
Output isn't correct |
2 |
Halted |
0 ms |
0 KB |
- |
# |
Verdict |
Execution time |
Memory |
Grader output |
1 |
Correct |
0 ms |
348 KB |
Output is correct |
2 |
Incorrect |
0 ms |
348 KB |
Output isn't correct |
3 |
Halted |
0 ms |
0 KB |
- |
# |
Verdict |
Execution time |
Memory |
Grader output |
1 |
Incorrect |
1 ms |
348 KB |
Output isn't correct |
2 |
Halted |
0 ms |
0 KB |
- |
# |
Verdict |
Execution time |
Memory |
Grader output |
1 |
Correct |
0 ms |
348 KB |
Output is correct |
2 |
Incorrect |
1 ms |
348 KB |
Output isn't correct |
3 |
Halted |
0 ms |
0 KB |
- |
# |
Verdict |
Execution time |
Memory |
Grader output |
1 |
Correct |
0 ms |
348 KB |
Output is correct |
2 |
Incorrect |
1 ms |
348 KB |
Output isn't correct |
3 |
Halted |
0 ms |
0 KB |
- |
# |
Verdict |
Execution time |
Memory |
Grader output |
1 |
Correct |
1 ms |
344 KB |
Output is correct |
2 |
Incorrect |
1 ms |
344 KB |
Output isn't correct |
3 |
Halted |
0 ms |
0 KB |
- |