Submission #553470

#	Time	Username	Problem	Language	Result	Execution time	Memory
553470		MohamedAhmed04	Asceticism (JOI18_asceticism)	C++14	49 / 100	42 ms	25016 KiB

asceticism

#include <bits/stdc++.h>

using namespace std ;

const int mod = 1e9 + 7 ;

int Add(int x , int y)
{
	int z = x + y ;
	if(z >= mod)
		z -= mod ;
	return z ;
}

int Sub(int x , int y)
{
	int z = x - y ;
	if(z < 0)
		z += mod ;
	return z ;
}

int Mul(int x , int y)
{
	return (x * 1ll * y) % mod ;
}

int powlog(int base , int power)
{
	if(power == 0)
		return 1 ;
	int x = powlog(base , power / 2) ;
	x = Mul(x , x) ;
	if(power & 1)
		x = Mul(x , base) ;
	return x ;
}

int modinv(int x)
{
	return powlog(x , mod-2) ;
}

int Div(int x , int y)
{
	return Mul(x , modinv(y)) ;
}

const int MAX = 3000 + 10 ;

int arr[MAX] ;
int n , k ;

int dp[MAX][MAX] ;

int main()
{
	ios_base::sync_with_stdio(0) ;
	cin.tie(0) ;
	cin>>n>>k ;
	dp[0][0] = 1 ;
	for(int i = 1 ; i <= n ; ++i)
	{
		for(int j = 1 ; j <= k ; ++j)
			dp[i][j] = Add(Mul(dp[i-1][j-1] , i-j+1) , Mul(dp[i-1][j] , j)) ;
	}
	return cout<<dp[n][k]<<"\n" , 0 ;
}		

• Subtask 1: 4 / 4
• Subtask 2: 20 / 20
• Subtask 3: 25 / 25
• Subtask 4: 0 / 51