Submission #1117755

#	Time	Username	Problem	Language	Result	Execution time	Memory
1117755		vjudge1	Kangaroo (CEOI16_kangaroo)	C++14	0 / 100	1 ms	336 KiB

kangaroo

#include <bits/stdc++.h>
using namespace std;

#define endl '\n'
#define pb push_back
#define F first
#define S second
#define ll long long
#define int ll
#define pii pair<int, int>
#define io ios_base::sync_with_stdio(0); cin.tie(0); cout.tie(0)
#define M_PI 3.14159265358979323846
#define all(v) v.begin(), v.end()
#define pss pair<string, string>
#define no cout<<"No"<<endl;
#define yes cout<<"Yes"<<endl;
#define imp cout<<-1<<endl;
#define flu cout.flush();
#define Endl endl

const int N = 100009;
const int mod = 1e9+7;

void solve(){
    int n, start, finish;
    cin>>n>>start>>finish;
    int dp[2005][3];
    int boyuk=0, kicik=0;
    if(finish<start){
        swap(finish, start);
    }
    kicik=start-1;
    boyuk=n-start-1;
    dp[1][0]=1;
    dp[1][1]=1;
    int q=0;
    for(int i=2; i<=n; i++){
        dp[i][0]=(dp[i-1][1]*(max(0ll, kicik-q)))%mod;
        dp[i][1]=(dp[i-1][0]*(max(0ll, boyuk-q)))%mod;
        //cout<<dp[i][0]<<" "<<dp[i][1]<<endl;
        q+=(i%2);

    }
    cout<<(dp[n-1][0]+dp[n-1][1])%mod;
}

signed main(){
    io;
    int t=1;
    //cin>>t;
    while(t--){
        solve();
    }
}

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