Submission #122093

#	Time	Username	Problem	Language	Result	Execution time	Memory
122093		rajarshi_basu	Kangaroo (CEOI16_kangaroo)	C++14	0 / 100	2 ms	384 KiB

kangaroo

#include <iostream>
#include <vector>
#include <set>
#include <iomanip>
#include <algorithm>
#include <functional>
#include <stdio.h>
#include <cmath>
#include <queue>
#include <string>
#include <map>
#include <fstream>
#include <complex>
#include <stack>
#include <set>

#define FOR(i,n) for(int i=0;i<n;i++)
#define FORE(i,a,b) for(int i=a;i<=b;i++)
#define ll long long int
#define vi vector<int>
#define ii pair<int,int>
#define pb push_back
#define mp make_pair
#define ff first
#define ss second
#define pll pair<ll,ll>
#define cd complex<double> 
#define ld long double
#define pld pair<ld,ld>
#define iii pair<ii,int>
#define vv vector

using namespace std;

const int MAXN = 2001;
const int MOD = 1e9 + 7;
ll dp[2001][2001];

int main(){
	int n,a,b;
	cin >> n >> a >> b;
	FOR(i,n)FOR(j,n)dp[i][j] = 0;
	a--;b--;
	dp[0][0] = 1;
	FOR(i,n){
		if(i == 0)continue;
		FOR(j,i+1){
			ll sum = 0;
			if(i%2 == 0){
				FORE(k,j,n-1){
					sum += dp[i-1][k];
					sum %= MOD;
				}
			}else{
				FORE(k,0,j-1){
					sum += dp[i-1][k];
					sum %= MOD;
				}
			}
			dp[i][j] = sum;
		}
	}

	FOR(i,n){
		FOR(j,n){
		//	cout << dp[i][j] << " ";
		}
		//cout << endl;
	}
	cout << dp[n-1][b] << endl;
	return 0;
}

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