Submission #577516

# Submission time Handle Problem Language Result Execution time Memory
577516 2022-06-15T03:38:59 Z amunduzbaev Fancy Fence (CEOI20_fancyfence) C++17
30 / 100
25 ms 5172 KB
#include "bits/stdc++.h"
using namespace std;
 
#define ar array
typedef int64_t ll;
#define int ll

const int N = 1e5 + 5;
const int mod = 1e9 + 7;
int h[N], w[N], pref[N];
int l[N], r[N];

signed main(){
	ios::sync_with_stdio(0); cin.tie(0);
	
	int n; cin>>n;
	for(int i=1;i<=n;i++){
		cin>>h[i];
	}
	for(int i=1;i<=n;i++){
		cin>>w[i];
		pref[i] = pref[i-1] + w[i];
	}
	
	vector<int> ss;
	for(int i=1;i<=n;i++){
		while(!ss.empty() && h[ss.back()] > h[i]){
			ss.pop_back();
		}
		
		if(!ss.empty()) l[i] = ss.back();
		else l[i] = 0;
		ss.push_back(i);
	}
	
	ss.clear();
	for(int i=n;i>0;i--){
		while(!ss.empty() && h[ss.back()] >= h[i]){
			ss.pop_back();
		}
		
		if(!ss.empty()) r[i] = ss.back();
		else r[i] = n + 1;
	}
	int inv = 5e8 + 4;
	int res = 0;
	for(int i=1;i<=n;i++){
		int L = (pref[i-1] - pref[l[i]]) % mod, R = (pref[r[i]-1] - pref[i]) % mod;
		int T = (pref[r[i] - 1] - pref[l[i]]) % mod;
		int tot = (T * 1ll * (T + 1) % mod - L * 1ll * (L + 1) % mod - R * 1ll * (R + 1) % mod + mod + mod) % mod;
		tot = tot * 1ll * inv % mod;
		T = (w[i] * 1ll * (w[i] + 1) / 2 % mod + L * 1ll * R % mod + w[i] * 1ll * (L + R) % mod) % mod;
		//~ cout<<T<<" "<<tot<<"\n";
		res = (res + tot * 1ll * (h[i] * 1ll * (h[i] + 1) % mod * inv % mod)) % mod;
	}
	
	cout<<res<<"\n";
}
# Verdict Execution time Memory Grader output
1 Correct 1 ms 340 KB Output is correct
2 Incorrect 1 ms 384 KB Output isn't correct
3 Halted 0 ms 0 KB -
# Verdict Execution time Memory Grader output
1 Incorrect 0 ms 340 KB Output isn't correct
2 Halted 0 ms 0 KB -
# Verdict Execution time Memory 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 -
# Verdict Execution time Memory Grader output
1 Correct 1 ms 340 KB Output is correct
2 Correct 3 ms 852 KB Output is correct
3 Correct 11 ms 2772 KB Output is correct
4 Correct 23 ms 5036 KB Output is correct
5 Correct 25 ms 5052 KB Output is correct
6 Correct 1 ms 340 KB Output is correct
# Verdict Execution time Memory Grader output
1 Correct 0 ms 340 KB Output is correct
2 Correct 1 ms 340 KB Output is correct
3 Correct 3 ms 852 KB Output is correct
4 Correct 12 ms 2772 KB Output is correct
5 Correct 25 ms 5156 KB Output is correct
6 Correct 25 ms 5172 KB Output is correct
7 Correct 1 ms 340 KB Output is correct
8 Correct 3 ms 852 KB Output is correct
9 Correct 15 ms 2808 KB Output is correct
10 Correct 22 ms 5084 KB Output is correct
11 Correct 22 ms 5164 KB Output is correct
12 Correct 1 ms 340 KB Output is correct
# Verdict Execution time Memory 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 -
# Verdict Execution time Memory Grader output
1 Correct 1 ms 340 KB Output is correct
2 Incorrect 1 ms 384 KB Output isn't correct
3 Halted 0 ms 0 KB -