Submission #479378

#	Submission time	Handle	Problem	Language	Result	Execution time	Memory
479378	2021-10-11T14:19:49 Z	8e7	Skyscraper (JOI16_skyscraper)	C++17	100 / 100	212 ms	2696 KB

skyscraper

//Challenge: Accepted
#include <iostream>
#include <fstream>
#include <vector>
#include <algorithm>
#include <cmath>
#include <utility>
#include <unordered_map>
#include <queue>
#include <stack>
#include <set>
#include <assert.h>
#include <iomanip>
using namespace std;
void debug() {cout << endl;}
template <class T, class ...U> void debug(T a, U ... b) { cout << a << " "; debug(b...);}
template <class T> void pary(T l, T r) {
	while (l != r) {cout << *l << " ";l++;}
	cout << endl;
}
#define ll long long
#define maxn 105
#define mod 1000000007
#define pii pair<int, int>
#define ff first
#define ss second
#define io ios_base::sync_with_stdio(0);cin.tie(0);
int dp[2][3][maxn][1005];
int a[maxn];
void madd(int &x, int v) {
	x += v - mod, x += mod & (x>>31);
}
int main() {
	int n, l;
	cin >> n >> l;
	for (int i = 0;i < n;i++) cin >> a[i];
	sort(a, a + n, [&](int x, int y){return x > y;});
	dp[0][0][0][0] = 1, dp[0][1][1][0] = 2, dp[0][2][2][0] = 1;
	for (int i = 0;i < n-1;i++) {
		int dif = a[i] - a[i+1];
		for (int c = 0;c < 3;c++) {
			for (int j = 1;j <= n;j++) {
				for (int k = 0;k <= l;k++) {
					int cost = k + (j-c) * 2 * dif + c * dif;
					if (cost > l) continue;
					//takes a gap in middle
					madd(dp[1][c][j-1][cost], (ll)dp[0][c][j][k] * (j - c) % mod);
					madd(dp[1][c][j][cost], (ll)dp[0][c][j][k] * (2 * (j-c) + c)% mod);
					madd(dp[1][c][j+1][cost], (ll)dp[0][c][j][k] * j % mod);
					//removes one of the sides
					if (c) {
						madd(dp[1][c-1][j-1][cost], (ll)dp[0][c][j][k] * c % mod);
						madd(dp[1][c-1][j][cost], (ll)dp[0][c][j][k] * c % mod);
					}
				}
			}
		}	
		for (int c = 0;c < 3;c++) {
			for (int j = 0;j <= n;j++) {
				for (int k = 0;k <= l;k++) dp[0][c][j][k] = dp[1][c][j][k], dp[1][c][j][k] = 0;
			}
		}	
		
	}
	int ans = 0;
	for (int i = 0;i <= l;i++) madd(ans, dp[0][0][0][i]);
	cout << ans << endl;
}
/*
 *
8 35
3 7 1 5 10 2 11 6
*/

Subtask #1

5.0 / 5.0

#	Verdict	Execution time	Memory	Grader output
1	Correct	1 ms	204 KB	Output is correct
2	Correct	1 ms	332 KB	Output is correct
3	Correct	1 ms	304 KB	Output is correct
4	Correct	1 ms	460 KB	Output is correct
5	Correct	1 ms	460 KB	Output is correct
6	Correct	2 ms	556 KB	Output is correct
7	Correct	1 ms	460 KB	Output is correct
8	Correct	1 ms	460 KB	Output is correct
9	Correct	2 ms	460 KB	Output is correct
10	Correct	1 ms	460 KB	Output is correct

Subtask #2

15.0 / 15.0

#	Verdict	Execution time	Memory	Grader output
1	Correct	1 ms	588 KB	Output is correct
2	Correct	2 ms	588 KB	Output is correct
3	Correct	1 ms	588 KB	Output is correct
4	Correct	1 ms	672 KB	Output is correct
5	Correct	1 ms	588 KB	Output is correct
6	Correct	1 ms	588 KB	Output is correct
7	Correct	1 ms	588 KB	Output is correct
8	Correct	1 ms	588 KB	Output is correct
9	Correct	1 ms	588 KB	Output is correct
10	Correct	1 ms	588 KB	Output is correct

Subtask #3

80.0 / 80.0

#	Verdict	Execution time	Memory	Grader output
1	Correct	1 ms	204 KB	Output is correct
2	Correct	1 ms	332 KB	Output is correct
3	Correct	1 ms	304 KB	Output is correct
4	Correct	1 ms	460 KB	Output is correct
5	Correct	1 ms	460 KB	Output is correct
6	Correct	2 ms	556 KB	Output is correct
7	Correct	1 ms	460 KB	Output is correct
8	Correct	1 ms	460 KB	Output is correct
9	Correct	2 ms	460 KB	Output is correct
10	Correct	1 ms	460 KB	Output is correct
11	Correct	1 ms	588 KB	Output is correct
12	Correct	2 ms	588 KB	Output is correct
13	Correct	1 ms	588 KB	Output is correct
14	Correct	1 ms	672 KB	Output is correct
15	Correct	1 ms	588 KB	Output is correct
16	Correct	1 ms	588 KB	Output is correct
17	Correct	1 ms	588 KB	Output is correct
18	Correct	1 ms	588 KB	Output is correct
19	Correct	1 ms	588 KB	Output is correct
20	Correct	1 ms	588 KB	Output is correct
21	Correct	2 ms	1228 KB	Output is correct
22	Correct	154 ms	2124 KB	Output is correct
23	Correct	169 ms	2696 KB	Output is correct
24	Correct	161 ms	2696 KB	Output is correct
25	Correct	212 ms	2696 KB	Output is correct
26	Correct	146 ms	2648 KB	Output is correct
27	Correct	57 ms	2680 KB	Output is correct
28	Correct	77 ms	2636 KB	Output is correct
29	Correct	150 ms	2608 KB	Output is correct
30	Correct	174 ms	2636 KB	Output is correct