Submission #156984

#	Time	Username	Problem	Language	Result	Execution time	Memory
156984		TadijaSebez	Kangaroo (CEOI16_kangaroo)	C++11	51 / 100	2044 ms	5712 KiB

kangaroo

#include <bits/stdc++.h>
using namespace std;
const int N=2050;
const int mod=1e9+7;
int add(int x, int y){ x+=y;return x>=mod?x-mod:x;}
int sub(int x, int y){ x-=y;return x<0?x+mod:x;}
int dp[2][N][N],tmp[2][N][N];
int main()
{
	int n,cs,cf;
	scanf("%i %i %i",&n,&cs,&cf);
    dp[0][1][1]=dp[1][1][1]=1;
    for(int l=2;l<=n;l++)
	{
		for(int i=1;i<=l;i++)
			for(int j=1;j<=l;j++)
				tmp[0][i][j]=tmp[1][i][j]=0;
		for(int i=1;i<=l-1;i++)
			for(int j=1;j<=l-1;j++)
				for(int k=1;k<=l;k++)
				{
					if(k<=j)
					{
						tmp[0][i+(k<=i)][k]=add(tmp[0][i+(k<=i)][k],dp[1][i][j]);
					}
					else
					{
						tmp[1][i+(k<=i)][k]=add(tmp[1][i+(k<=i)][k],dp[0][i][j]);
					}
				}
		for(int i=1;i<=l;i++)
			for(int j=1;j<=l;j++)
			{
				dp[0][i][j]=tmp[0][i][j];
				dp[1][i][j]=tmp[1][i][j];
			}
	}
	int ans=add(dp[0][cs][cf],dp[1][cs][cf]);
	printf("%i\n",ans);
	return 0;
}

Compilation message (stderr)

kangaroo.cpp: In function 'int main()':
kangaroo.cpp:11:7: warning: ignoring return value of 'int scanf(const char*, ...)', declared with attribute warn_unused_result [-Wunused-result]
  scanf("%i %i %i",&n,&cs,&cf);
  ~~~~~^~~~~~~~~~~~~~~~~~~~~~~

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