oj.uz

답안 #461335

# 제출 시각 아이디 문제 언어 결과 실행 시간 메모리
461335 2021-08-09T21:41:08 Z izhang05 캥거루 (CEOI16_kangaroo) C++17
100 / 100
 38 ms 31684 KB 
#include <bits/stdc++.h>

using namespace std;

//#define DEBUG
void setIO(const string &name) {
    ios_base::sync_with_stdio(false);
    cin.tie(nullptr);
    cin.exceptions(istream::failbit);
#ifdef LOCAL
    freopen((name + ".in").c_str(), "r", stdin);
    freopen((name + ".out").c_str(), "w", stdout);
    freopen((name + ".out").c_str(), "w", stderr);
#endif
}

const int inf = 0x3f3f3f3f, mod = 1e9 + 7, maxn = 2005;
const long long INFL = 0x3f3f3f3f3f3f3f3f;

long long dp[maxn][maxn];


int main() {
    setIO("1");

    int n, start, end;
    cin >> n >> start >> end;
    dp[1][1] = 1;
    for (int i = 2; i <= n; ++i) {
        for (int j = 1; j <= n; ++j) {
            long long &cur = dp[i][j];
            if (i == start || i == end) {
                cur = (dp[i - 1][j] + dp[i - 1][j - 1]) % mod;
            } else {
                cur += j * dp[i - 1][j + 1];
                cur %= mod;
                cur += (j - (i > start) - (i > end)) * dp[i - 1][j - 1];
                cur %= mod;
            }
        }
    }
    cout << dp[n][1] << "\n";
    return 0;
}

Subtask #1
6.0 / 6.0

# 결과 실행 시간 메모리 Grader output
1 Correct 1 ms 332 KB Output is correct
2 Correct 0 ms 332 KB Output is correct

Subtask #2
30.0 / 30.0

# 결과 실행 시간 메모리 Grader output
1 Correct 1 ms 332 KB Output is correct
2 Correct 0 ms 332 KB Output is correct
3 Correct 1 ms 332 KB Output is correct
4 Correct 1 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 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 460 KB Output is correct

Subtask #3
15.0 / 15.0

# 결과 실행 시간 메모리 Grader output
1 Correct 1 ms 332 KB Output is correct
2 Correct 0 ms 332 KB Output is correct
3 Correct 1 ms 332 KB Output is correct
4 Correct 1 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 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 460 KB Output is correct
12 Correct 2 ms 1356 KB Output is correct
13 Correct 2 ms 1344 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 1 ms 332 KB Output is correct
2 Correct 0 ms 332 KB Output is correct
3 Correct 1 ms 332 KB Output is correct
4 Correct 1 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 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 460 KB Output is correct
12 Correct 2 ms 1356 KB Output is correct
13 Correct 2 ms 1344 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 6220 KB Output is correct
22 Correct 7 ms 6860 KB Output is correct
23 Correct 8 ms 7756 KB Output is correct
24 Correct 38 ms 31680 KB Output is correct
25 Correct 38 ms 31656 KB Output is correct
26 Correct 38 ms 31684 KB Output is correct
27 Correct 37 ms 31532 KB Output is correct
28 Correct 25 ms 23748 KB Output is correct