답안 #493911

#	제출 시각	아이디	문제	언어	결과	실행 시간	메모리
493911	2021-12-13T10:55:19 Z	khoabright	캥거루 (CEOI16_kangaroo)	C++17	100 / 100	23 ms	22980 KB

kangaroo

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

#define int long long
#define ll long long
#define pii pair<int, int>
#define ff first
#define ss second
#define pb push_back
#define rep(i, a, b) for (int i = (int)a; i <= (int)b; ++i)
#define rep1(i, a, b) for (int i = (int)a; i >= (int)b; --i)
#define all(x) x.begin(), x.end()

const int N = 2e3 + 5;
const int mod = 1e9 + 7;

int dp[N][N];

signed main() {
    int n, a, b; cin >> n >> a >> b;
    dp[1][1] = 1;
    rep(i, 1, n - 1) rep(j, 1, i) {
        if (i + 1 == a || i + 1 == b) {
            (dp[i + 1][j] += dp[i][j]) %= mod;
            (dp[i + 1][j + 1] += dp[i][j]) %= mod;
        }

        else {
            // merge two components
            (dp[i + 1][j - 1] += dp[i][j] * (j - 1)) %= mod;

            // create a new component
            (dp[i + 1][j + 1] += (dp[i][j] * (j + 1 - (i + 1 > a) - (i + 1 > b)))) %= mod;
        }
    }

    cout << dp[n][1];
}

Subtask #1

6.0 / 6.0

#	결과	실행 시간	메모리	Grader output
1	Correct	0 ms	204 KB	Output is correct
2	Correct	0 ms	204 KB	Output is correct

Subtask #2

30.0 / 30.0

#	결과	실행 시간	메모리	Grader output
1	Correct	0 ms	204 KB	Output is correct
2	Correct	0 ms	204 KB	Output is correct
3	Correct	0 ms	332 KB	Output is correct
4	Correct	0 ms	460 KB	Output is correct
5	Correct	1 ms	460 KB	Output is correct
6	Correct	1 ms	460 KB	Output is correct
7	Correct	1 ms	332 KB	Output is correct
8	Correct	1 ms	432 KB	Output is correct
9	Correct	1 ms	460 KB	Output is correct
10	Correct	1 ms	460 KB	Output is correct
11	Correct	1 ms	324 KB	Output is correct

Subtask #3

15.0 / 15.0

#	결과	실행 시간	메모리	Grader output
1	Correct	0 ms	204 KB	Output is correct
2	Correct	0 ms	204 KB	Output is correct
3	Correct	0 ms	332 KB	Output is correct
4	Correct	0 ms	460 KB	Output is correct
5	Correct	1 ms	460 KB	Output is correct
6	Correct	1 ms	460 KB	Output is correct
7	Correct	1 ms	332 KB	Output is correct
8	Correct	1 ms	432 KB	Output is correct
9	Correct	1 ms	460 KB	Output is correct
10	Correct	1 ms	460 KB	Output is correct
11	Correct	1 ms	324 KB	Output is correct
12	Correct	1 ms	1228 KB	Output is correct
13	Correct	1 ms	1100 KB	Output is correct
14	Correct	1 ms	1228 KB	Output is correct
15	Correct	1 ms	1228 KB	Output is correct
16	Correct	1 ms	1228 KB	Output is correct
17	Correct	2 ms	1228 KB	Output is correct
18	Correct	1 ms	1100 KB	Output is correct
19	Correct	1 ms	1228 KB	Output is correct
20	Correct	1 ms	1228 KB	Output is correct

Subtask #4

49.0 / 49.0

#	결과	실행 시간	메모리	Grader output
1	Correct	0 ms	204 KB	Output is correct
2	Correct	0 ms	204 KB	Output is correct
3	Correct	0 ms	332 KB	Output is correct
4	Correct	0 ms	460 KB	Output is correct
5	Correct	1 ms	460 KB	Output is correct
6	Correct	1 ms	460 KB	Output is correct
7	Correct	1 ms	332 KB	Output is correct
8	Correct	1 ms	432 KB	Output is correct
9	Correct	1 ms	460 KB	Output is correct
10	Correct	1 ms	460 KB	Output is correct
11	Correct	1 ms	324 KB	Output is correct
12	Correct	1 ms	1228 KB	Output is correct
13	Correct	1 ms	1100 KB	Output is correct
14	Correct	1 ms	1228 KB	Output is correct
15	Correct	1 ms	1228 KB	Output is correct
16	Correct	1 ms	1228 KB	Output is correct
17	Correct	2 ms	1228 KB	Output is correct
18	Correct	1 ms	1100 KB	Output is correct
19	Correct	1 ms	1228 KB	Output is correct
20	Correct	1 ms	1228 KB	Output is correct
21	Correct	4 ms	4556 KB	Output is correct
22	Correct	4 ms	5036 KB	Output is correct
23	Correct	4 ms	5452 KB	Output is correct
24	Correct	21 ms	22952 KB	Output is correct
25	Correct	20 ms	22856 KB	Output is correct
26	Correct	23 ms	22980 KB	Output is correct
27	Correct	20 ms	22796 KB	Output is correct
28	Correct	14 ms	15040 KB	Output is correct