Submission #1118325

#	Time	Username	Problem	Language	Result	Execution time	Memory
1118325		vjudge1	Kangaroo (CEOI16_kangaroo)	C++17	0 / 100	1 ms	348 KiB

kangaroo

#include<bits/stdc++.h>

#define ll long long
#define pb push_back
#define in insert
#define fi first
#define se second
#define vl vector<ll>
#define all(v) v.begin(), v.end()
#define endl "\n"

using namespace std;
const int sz = 2005; /// mind this $$
const int MAX = 2e6 + 123;
const int BS = 61;
const ll inf = 1e17;
const int mod = 998244353;
ll dp[2][sz][sz];
void solve(){
    ll n, k, i, j;
    cin >> n >> k;
    dp[0][1][1] = 1;
    for(i = 2; i <= n; i++){
        for(j = 1; j <= n; j++){
            for(int t = 0; t < 2; t++){
                int open = j - t;
                if(open >= k){
                    continue;
                }
                dp[t][i][j] = (dp[t][i][j] + (dp[t][i - 1][j - 1] * (j - t)) % mod) % mod;
                dp[t][i][j] = (dp[t][i][j] + (dp[t][i - 1][j + 1] * j) % mod) % mod;
                if(open + 1 < k){
                    dp[t][i][j] = (dp[t][i][j] + (dp[t][i - 1][j] * (j - t)) % mod) % mod;
                }
                dp[t][i][j] = (dp[t][i][j] + (dp[t][i - 1][j] * j) % mod) % mod;
                if(t == 1){
                    dp[t][i][j] = (dp[0][i - 1][j] + dp[0][i - 1][j - 1]) % mod;
                }
            }
        }
    }
    cout << dp[n][1] << endl;

}
int main(){
    ios_base::sync_with_stdio(false);
    cin.tie(0);
    cout.tie(0);
    ll t = 1;
    // cin >> t;
    while(t--){
        solve();
    }
}

/*

*/

• Subtask 1: 0 / 6
• Subtask 2: 0 / 30
• Subtask 3: 0 / 15
• Subtask 4: 0 / 49