제출 #1005715

#	제출 시각	아이디	문제	언어	결과	실행 시간	메모리
1005715		0pt1mus23	캥거루 (CEOI16_kangaroo)	C++14	100 / 100	28 ms	31836 KiB

kangaroo

#pragma GCC optimize("O3", "inline")
#include <bits/stdc++.h>
using namespace std;
#define ins insert
#define pb push_back
#define int long long int
#define pii pair<int, int>
#define endl '\n'
#define drop(x) cout<<(x)<<endl; return;
#define all(x) x.begin(),x.end()
const int mod = 1e9 +7, sze = 1e5+10, inf = 2e18, prime = 23;

int dp[2005][2005];


void mal(){
    dp[1][1]=1;
    int n,a,b;cin>>n>>a>>b;
    for(int i=2;i<=n;i++){
        for(int j=1;j<=n;j++){
            if(i==a || i==b){
                dp[i][j] = (dp[i][j] + dp[i-1][j-1] + dp[i-1][j] +mod)%mod;
            }
            else{
                dp[i][j]= (dp[i-1][j+1]*j + dp[i][j] + mod)%mod;
                dp[i][j] = (dp[i][j] + dp[i-1][j-1] * (j - (i>a) - (i>b)) + mod)%mod; // a ni gormusuk, a dan arxaya qoyammariq, b ni gormusuk, b den arxaya qoyammariq, 2 hours
            }
        }  
    }
    drop(dp[n][1]);
}   

signed main() {
    cin.tie(0)->sync_with_stdio(0);
    int tt = 1;
    // cin>>tt;
    
    while(tt--){
        mal();        
    }
}

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