Submission #3820103

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Source Code Expand

#include <cstdio>
#define rep(i,j,k) for (i=j;i<=k;i++)
using namespace std;
const int N=3e3+5,mod=1e9+7;
int n,m,i,j,p,ans,f[N][N][2];
void updata(int &x,int y) { x+=y; if (x>=mod) x-=mod; }
int main()
{
//	freopen("piling.in","r",stdin);
//	freopen("piling.out","w",stdout);
	scanf("%d%d",&n,&m);
	f[0][0][1]=1;
	rep(i,1,n) f[0][i][0]=1;
	rep(i,0,m-1)
		rep(j,0,n)
			rep(p,0,1)
			if (f[i][j][p])
			{
				if (j) updata(f[i+1][j-1][p|(j==1)],f[i][j][p]);
				if (j) updata(f[i+1][j][p|(j==1)],f[i][j][p]);
				if (n-j) updata(f[i+1][j][p],f[i][j][p]);
				if (n-j) updata(f[i+1][j+1][p],f[i][j][p]);
			}
	rep(i,0,n)
		updata(ans,f[m][i][1]);
	printf("%d\n",ans);
	return 0;
}

Submission Info

Compile Error

./Main.cpp: In function ‘int main()’:
./Main.cpp:11:21: warning: ignoring return value of ‘int scanf(const char*, ...)’, declared with attribute warn_unused_result [-Wunused-result]
  scanf("%d%d",&n,&m);
                     ^

Judge Result