oj.uz

답안 #900625

# 제출 시각 아이디 문제 언어 결과 실행 시간 메모리
900625 2024-01-08T17:15:01 Z warner1129 캥거루 (CEOI16_kangaroo) C++17
100 / 100
 33 ms 488 KB 
#include <bits/stdc++.h>
 
using namespace std;

 
#ifdef LOCAL
template<class... T> void dbg(T... x) { char e{}; ((cerr << e << x, e = ' '), ...); }
#define debug(x...) dbg(#x, '=', x, '\n')
#else
#define debug(...) ((void)0)
#endif
 
#define all(v) (v).begin(), (v).end()
#define rall(v) (v).rbegin(), (v).rend()
#define ff first
#define ss second
 
using u32 = unsigned int;
using i64 = long long;
using u64 = unsigned long long;
using i128 = __int128;
using u128 = unsigned __int128;
 
template<class T> inline constexpr T inf = numeric_limits<T>::max() / 2;
constexpr int mod = 1e9 + 7, inv2 = (mod + 1) / 2;
 
template<class T> bool chmin(T &a, T b) { return (b < a and (a = b, true)); }
template<class T> bool chmax(T &a, T b) { return (a < b and (a = b, true)); }

void solve() {
    int n, s, t;
    cin >> n >> s >> t;

    int op = s > 1;
    int ed = t > 1;
    vector dp(n + 1, array<i64, 3>{});
    
    dp[1][0] = 1;
    
    for (int i = 2; i <= n; i++) {
        decltype(dp) f(n + 1, array<i64, 3>{});
        
        for (int j = 1; j < i; j++) {
            if (i == s or i == t) {
                f[j][1] += dp[j][0];
                f[j][2] += dp[j][1];
                f[j + 1][0] += dp[j][0];
                f[j + 1][1] += dp[j][1];
                f[j + 1][2] += dp[j][2];
            } else {
                for (int x : {0, 1, 2}) {
                    f[j - 1][x] += dp[j][x] * (j - 1);
                    f[j + 1][x] += dp[j][x] * (i - 1 - j + op + ed - x);
                }
            }
        }

        if (s == i) op = 0;
        if (t == i) ed = 0;
        
        dp.swap(f);
        for (auto &x : dp)
            for (auto &v : x) v %= mod;
    }

    cout << (dp[1][0] + dp[1][1] + dp[1][2]) % mod << '\n';
}
 
signed main() {
    cin.tie(0)->sync_with_stdio(false);
    cin.exceptions(cin.failbit);
    int T = 1;
    // cin >> T;
    while (T--) {
        solve();
    }
    return 0;
}

Subtask #1
6.0 / 6.0

# 결과 실행 시간 메모리 Grader output
1 Correct 0 ms 348 KB Output is correct
2 Correct 0 ms 348 KB Output is correct

Subtask #2
30.0 / 30.0

# 결과 실행 시간 메모리 Grader output
1 Correct 0 ms 348 KB Output is correct
2 Correct 0 ms 348 KB Output is correct
3 Correct 0 ms 344 KB Output is correct
4 Correct 0 ms 348 KB Output is correct
5 Correct 0 ms 348 KB Output is correct
6 Correct 0 ms 348 KB Output is correct
7 Correct 0 ms 348 KB Output is correct
8 Correct 0 ms 348 KB Output is correct
9 Correct 0 ms 348 KB Output is correct
10 Correct 0 ms 348 KB Output is correct
11 Correct 0 ms 348 KB Output is correct

Subtask #3
15.0 / 15.0

# 결과 실행 시간 메모리 Grader output
1 Correct 0 ms 348 KB Output is correct
2 Correct 0 ms 348 KB Output is correct
3 Correct 0 ms 344 KB Output is correct
4 Correct 0 ms 348 KB Output is correct
5 Correct 0 ms 348 KB Output is correct
6 Correct 0 ms 348 KB Output is correct
7 Correct 0 ms 348 KB Output is correct
8 Correct 0 ms 348 KB Output is correct
9 Correct 0 ms 348 KB Output is correct
10 Correct 0 ms 348 KB Output is correct
11 Correct 0 ms 348 KB Output is correct
12 Correct 1 ms 348 KB Output is correct
13 Correct 1 ms 348 KB Output is correct
14 Correct 1 ms 348 KB Output is correct
15 Correct 1 ms 348 KB Output is correct
16 Correct 1 ms 348 KB Output is correct
17 Correct 1 ms 348 KB Output is correct
18 Correct 1 ms 348 KB Output is correct
19 Correct 1 ms 348 KB Output is correct
20 Correct 1 ms 348 KB Output is correct

Subtask #4
49.0 / 49.0

# 결과 실행 시간 메모리 Grader output
1 Correct 0 ms 348 KB Output is correct
2 Correct 0 ms 348 KB Output is correct
3 Correct 0 ms 344 KB Output is correct
4 Correct 0 ms 348 KB Output is correct
5 Correct 0 ms 348 KB Output is correct
6 Correct 0 ms 348 KB Output is correct
7 Correct 0 ms 348 KB Output is correct
8 Correct 0 ms 348 KB Output is correct
9 Correct 0 ms 348 KB Output is correct
10 Correct 0 ms 348 KB Output is correct
11 Correct 0 ms 348 KB Output is correct
12 Correct 1 ms 348 KB Output is correct
13 Correct 1 ms 348 KB Output is correct
14 Correct 1 ms 348 KB Output is correct
15 Correct 1 ms 348 KB Output is correct
16 Correct 1 ms 348 KB Output is correct
17 Correct 1 ms 348 KB Output is correct
18 Correct 1 ms 348 KB Output is correct
19 Correct 1 ms 348 KB Output is correct
20 Correct 1 ms 348 KB Output is correct
21 Correct 3 ms 348 KB Output is correct
22 Correct 3 ms 488 KB Output is correct
23 Correct 4 ms 456 KB Output is correct
24 Correct 26 ms 348 KB Output is correct
25 Correct 33 ms 348 KB Output is correct
26 Correct 25 ms 344 KB Output is correct
27 Correct 25 ms 348 KB Output is correct
28 Correct 15 ms 344 KB Output is correct