답안 #493910

#	제출 시각	아이디	문제	언어	결과	실행 시간	메모리
493910	2021-12-13T10:54:47 Z	khoabright	캥거루 (CEOI16_kangaroo)	C++17	100 / 100	35 ms	31608 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];

main() {
    int n, a, b; cin >> n >> a >> b;
    dp[1][1] = 1;
    rep(i, 1, n - 1) rep(j, 1, n) {
        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];
}

Compilation message

kangaroo.cpp:19:1: warning: ISO C++ forbids declaration of 'main' with no type [-Wreturn-type]
   19 | main() {
      | ^~~~

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	1 ms	332 KB	Output is correct
4	Correct	1 ms	424 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	460 KB	Output is correct
8	Correct	1 ms	460 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	424 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	1 ms	332 KB	Output is correct
4	Correct	1 ms	424 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	460 KB	Output is correct
8	Correct	1 ms	460 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	424 KB	Output is correct
12	Correct	1 ms	1356 KB	Output is correct
13	Correct	1 ms	1228 KB	Output is correct
14	Correct	1 ms	1356 KB	Output is correct
15	Correct	1 ms	1356 KB	Output is correct
16	Correct	1 ms	1356 KB	Output is correct
17	Correct	1 ms	1356 KB	Output is correct
18	Correct	1 ms	1228 KB	Output is correct
19	Correct	1 ms	1356 KB	Output is correct
20	Correct	1 ms	1356 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	1 ms	332 KB	Output is correct
4	Correct	1 ms	424 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	460 KB	Output is correct
8	Correct	1 ms	460 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	424 KB	Output is correct
12	Correct	1 ms	1356 KB	Output is correct
13	Correct	1 ms	1228 KB	Output is correct
14	Correct	1 ms	1356 KB	Output is correct
15	Correct	1 ms	1356 KB	Output is correct
16	Correct	1 ms	1356 KB	Output is correct
17	Correct	1 ms	1356 KB	Output is correct
18	Correct	1 ms	1228 KB	Output is correct
19	Correct	1 ms	1356 KB	Output is correct
20	Correct	1 ms	1356 KB	Output is correct
21	Correct	6 ms	6324 KB	Output is correct
22	Correct	6 ms	6860 KB	Output is correct
23	Correct	7 ms	7756 KB	Output is correct
24	Correct	31 ms	31608 KB	Output is correct
25	Correct	34 ms	31556 KB	Output is correct
26	Correct	35 ms	31572 KB	Output is correct
27	Correct	34 ms	31416 KB	Output is correct
28	Correct	28 ms	23760 KB	Output is correct