Submission #306957

#	Submission time	Handle	Problem	Language	Result	Execution time	Memory
306957	2020-09-26T15:11:56 Z	two_sides	Skyscraper (JOI16_skyscraper)	C++17	100 / 100	362 ms	173948 KB

skyscraper

#include <bits/stdc++.h>
using namespace std;

using ll = long long;

const int L = 1005;
const int N = 105;
const int MOD = 1e9 + 7;

int madd(int x, int y) {
    if ((x += y) >= MOD) x -= MOD;
    return x;
}

int mmul(int x, int y) {
    return ll(x) * y % MOD;
}

int n, l, dp[N][L][N][2][2], a[N];

int rec(int i, int tot,
int seg, int kl, int kr) {
    int nxt = tot + (seg * 2 + kl
    + kr) * abs(a[i + 1] - a[i]);
    if (nxt > l || seg < 0) return 0;
    if (i == n - 1) return seg == 0;
    int &res = dp[i][tot][seg][kl][kr];
    if (~res) return res;
    res = rec(i + 1, nxt, seg, 1, kr);
    res = madd(res,
    rec(i + 1, nxt, seg, kl, 1));
    res = madd(res, mmul(rec(i + 1,
    nxt, seg - 1, 1, kr), seg));
    res = madd(res, mmul(rec(i + 1,
    nxt, seg - 1, kl, 1), seg));
    res = madd(res, rec(i + 1,
    nxt, seg + 1, kl, kr));
    res = madd(res, mmul(rec(i + 1,
    nxt, seg, kl, kr), seg * 2));
    res = madd(res, mmul(rec(i + 1, nxt,
    seg - 1, kl, kr), seg * (seg - 1)));
    return res;
}

int main() {
    cin.tie(0)->sync_with_stdio(0);
    cin >> n >> l;
    for (int i = 1; i <= n; i++)
        cin >> a[i];
    sort(a + 1, a + n + 1);
    memset(dp, -1, sizeof dp);
    a[0] = a[1];
    cout << rec(0, 0, 0, 0, 0) << '\n';
}

Subtask #1

5.0 / 5.0

#	Verdict	Execution time	Memory	Grader output
1	Correct	94 ms	173816 KB	Output is correct
2	Correct	97 ms	173816 KB	Output is correct
3	Correct	96 ms	173944 KB	Output is correct
4	Correct	94 ms	173820 KB	Output is correct
5	Correct	96 ms	173816 KB	Output is correct
6	Correct	96 ms	173816 KB	Output is correct
7	Correct	98 ms	173944 KB	Output is correct
8	Correct	95 ms	173816 KB	Output is correct
9	Correct	103 ms	173812 KB	Output is correct
10	Correct	98 ms	173816 KB	Output is correct

Subtask #2

15.0 / 15.0

#	Verdict	Execution time	Memory	Grader output
1	Correct	98 ms	173948 KB	Output is correct
2	Correct	98 ms	173816 KB	Output is correct
3	Correct	96 ms	173816 KB	Output is correct
4	Correct	99 ms	173816 KB	Output is correct
5	Correct	98 ms	173816 KB	Output is correct
6	Correct	102 ms	173816 KB	Output is correct
7	Correct	100 ms	173816 KB	Output is correct
8	Correct	95 ms	173816 KB	Output is correct
9	Correct	101 ms	173816 KB	Output is correct
10	Correct	98 ms	173816 KB	Output is correct

Subtask #3

80.0 / 80.0

#	Verdict	Execution time	Memory	Grader output
1	Correct	94 ms	173816 KB	Output is correct
2	Correct	97 ms	173816 KB	Output is correct
3	Correct	96 ms	173944 KB	Output is correct
4	Correct	94 ms	173820 KB	Output is correct
5	Correct	96 ms	173816 KB	Output is correct
6	Correct	96 ms	173816 KB	Output is correct
7	Correct	98 ms	173944 KB	Output is correct
8	Correct	95 ms	173816 KB	Output is correct
9	Correct	103 ms	173812 KB	Output is correct
10	Correct	98 ms	173816 KB	Output is correct
11	Correct	98 ms	173948 KB	Output is correct
12	Correct	98 ms	173816 KB	Output is correct
13	Correct	96 ms	173816 KB	Output is correct
14	Correct	99 ms	173816 KB	Output is correct
15	Correct	98 ms	173816 KB	Output is correct
16	Correct	102 ms	173816 KB	Output is correct
17	Correct	100 ms	173816 KB	Output is correct
18	Correct	95 ms	173816 KB	Output is correct
19	Correct	101 ms	173816 KB	Output is correct
20	Correct	98 ms	173816 KB	Output is correct
21	Correct	98 ms	173820 KB	Output is correct
22	Correct	362 ms	173816 KB	Output is correct
23	Correct	312 ms	173816 KB	Output is correct
24	Correct	292 ms	173816 KB	Output is correct
25	Correct	314 ms	173816 KB	Output is correct
26	Correct	294 ms	173848 KB	Output is correct
27	Correct	158 ms	173816 KB	Output is correct
28	Correct	183 ms	173816 KB	Output is correct
29	Correct	313 ms	173816 KB	Output is correct
30	Correct	330 ms	173816 KB	Output is correct