oj.uz

Submission #1021095

# Submission time Handle Problem Language Result Execution time Memory
1021095 2024-07-12T13:57:35 Z nrg_studio Fancy Fence (CEOI20_fancyfence) C++17
100 / 100
 43 ms 9424 KB 
#include <bits/stdc++.h>
using namespace std;

#define ll long long
#define pb push_back
#define FOR(i, a, b, s) for (int i = (a); i < (b); i += s)
#define F0R(i, a) for (int i = 0; i < (a); i++)

ll mod = 1e9+7;

int main() {
	ios::sync_with_stdio(false); cin.tie(0);
	int n; cin >> n;
	vector<ll> h(n+2,0),w(n+2,0);
	unordered_map<int,int> bounds;
	F0R(i,n) {cin >> h[i+1]; bounds[h[i+1]]=INT_MIN;}
	F0R(i,n) {cin >> w[i+1]; w[i+1]=(w[i+1]+w[i])%mod;} // ps
	
	vector<int> r(n+2,n+1),l(n+2,0);
	// nearest smaller values on h (or 0 if it doesn't exist)
	stack<int> s,s2; s.push(0); s2.push(n+1);
	FOR(i,1,n+1,1) {
		int j = n-i+1;
		while (s.size() && h[s.top()]>=h[i]) {s.pop();}
		l[i] = s.top(); s.push(i);
		while (s2.size() && h[s2.top()]>=h[j]) {s2.pop();}
		r[j] = s2.top(); s2.push(j);
	}

	// store a left right bound for all h (offline) to avoid equal heights recalc
	// update bounds if disjoint

	// otherwise find # of subgrids, and then subtract number of subgrids distinctly
	// in the max(right,left) smallest values
	ll ans = 0;
	auto add = [&](ll a, ll b)->ll {return (a+b)%mod;};
	auto sub = [&](ll a, ll b)->ll {return (a+mod-b)%mod;};
	auto mult = [&](ll a, ll b)->ll {return a*b%mod;};
	auto subgrids = [&](ll width, ll height)->ll {return mult(mult(width*width%mod+width%mod,height*height%mod+height%mod),250000002);};
	
	FOR(i,1,n+1,1) {
		if (l[i]>=bounds[h[i]]) {
			bounds[h[i]]=r[i];
			ll width = sub(w[r[i]-1],w[l[i]]); 
			ll height = h[i], extra = max(h[r[i]],h[l[i]]);
			ans = add(ans,subgrids(width,height));
			ans = sub(ans,subgrids(width,extra));
		}
	} cout << ans << '\n';
}

Subtask #1
0.0 / 0.0

# Verdict Execution time Memory Grader output
1 Correct 0 ms 344 KB Output is correct
2 Correct 1 ms 348 KB Output is correct

Subtask #2
12.0 / 12.0

# Verdict Execution time Memory Grader output
1 Correct 0 ms 344 KB Output is correct
2 Correct 0 ms 348 KB Output is correct
3 Correct 0 ms 348 KB Output is correct
4 Correct 0 ms 348 KB Output is correct
5 Correct 0 ms 348 KB Output is correct

Subtask #3
13.0 / 13.0

# Verdict Execution time Memory Grader output
1 Correct 0 ms 348 KB Output is correct
2 Correct 0 ms 348 KB Output is correct
3 Correct 7 ms 2232 KB Output is correct
4 Correct 14 ms 3940 KB Output is correct
5 Correct 16 ms 4000 KB Output is correct
6 Correct 14 ms 3944 KB Output is correct

Subtask #4
15.0 / 15.0

# Verdict Execution time Memory Grader output
1 Correct 1 ms 348 KB Output is correct
2 Correct 2 ms 860 KB Output is correct
3 Correct 8 ms 2488 KB Output is correct
4 Correct 19 ms 4700 KB Output is correct
5 Correct 17 ms 4700 KB Output is correct
6 Correct 0 ms 344 KB Output is correct

Subtask #5
15.0 / 15.0

# Verdict Execution time Memory Grader output
1 Correct 0 ms 344 KB Output is correct
2 Correct 0 ms 604 KB Output is correct
3 Correct 2 ms 860 KB Output is correct
4 Correct 8 ms 2544 KB Output is correct
5 Correct 16 ms 4700 KB Output is correct
6 Correct 16 ms 4872 KB Output is correct
7 Correct 1 ms 348 KB Output is correct
8 Correct 3 ms 1116 KB Output is correct
9 Correct 11 ms 3420 KB Output is correct
10 Correct 31 ms 9320 KB Output is correct
11 Correct 33 ms 9424 KB Output is correct
12 Correct 0 ms 352 KB Output is correct

Subtask #6
18.0 / 18.0

# Verdict Execution time Memory Grader output
1 Correct 0 ms 348 KB Output is correct
2 Correct 1 ms 348 KB Output is correct
3 Correct 0 ms 348 KB Output is correct
4 Correct 1 ms 352 KB Output is correct
5 Correct 0 ms 352 KB Output is correct
6 Correct 0 ms 348 KB Output is correct
7 Correct 1 ms 348 KB Output is correct
8 Correct 0 ms 348 KB Output is correct
9 Correct 1 ms 348 KB Output is correct
10 Correct 0 ms 348 KB Output is correct
11 Correct 0 ms 456 KB Output is correct
12 Correct 0 ms 348 KB Output is correct
13 Correct 1 ms 344 KB Output is correct
14 Correct 1 ms 344 KB Output is correct
15 Correct 1 ms 348 KB Output is correct
16 Correct 0 ms 348 KB Output is correct

Subtask #7
27.0 / 27.0

# Verdict Execution time Memory Grader output
1 Correct 0 ms 344 KB Output is correct
2 Correct 1 ms 348 KB Output is correct
3 Correct 0 ms 348 KB Output is correct
4 Correct 1 ms 348 KB Output is correct
5 Correct 0 ms 348 KB Output is correct
6 Correct 0 ms 348 KB Output is correct
7 Correct 0 ms 348 KB Output is correct
8 Correct 0 ms 348 KB Output is correct
9 Correct 0 ms 348 KB Output is correct
10 Correct 0 ms 348 KB Output is correct
11 Correct 7 ms 2136 KB Output is correct
12 Correct 18 ms 3944 KB Output is correct
13 Correct 14 ms 3944 KB Output is correct
14 Correct 13 ms 3820 KB Output is correct
15 Correct 0 ms 348 KB Output is correct
16 Correct 2 ms 860 KB Output is correct
17 Correct 8 ms 2396 KB Output is correct
18 Correct 16 ms 4700 KB Output is correct
19 Correct 18 ms 4700 KB Output is correct
20 Correct 1 ms 348 KB Output is correct
21 Correct 3 ms 1116 KB Output is correct
22 Correct 11 ms 3520 KB Output is correct
23 Correct 31 ms 9416 KB Output is correct
24 Correct 41 ms 9424 KB Output is correct
25 Correct 1 ms 344 KB Output is correct
26 Correct 0 ms 348 KB Output is correct
27 Correct 1 ms 348 KB Output is correct
28 Correct 1 ms 428 KB Output is correct
29 Correct 0 ms 348 KB Output is correct
30 Correct 3 ms 1116 KB Output is correct
31 Correct 4 ms 1116 KB Output is correct
32 Correct 10 ms 2396 KB Output is correct
33 Correct 16 ms 4716 KB Output is correct
34 Correct 42 ms 9008 KB Output is correct
35 Correct 20 ms 4444 KB Output is correct
36 Correct 43 ms 9156 KB Output is correct
37 Correct 28 ms 7268 KB Output is correct
38 Correct 0 ms 348 KB Output is correct
39 Correct 25 ms 6876 KB Output is correct
40 Correct 33 ms 9164 KB Output is correct
41 Correct 31 ms 9164 KB Output is correct
42 Correct 33 ms 9424 KB Output is correct