Submission #1868951

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Source Code Expand

#include <cstdio>
const int mo=1000000007;
int f[3005][3005][2];
int main(){
	int n,m;
	scanf("%d%d\n",&n,&m);
	for (int i=0;i<=n;i++) f[0][i][i==0]=1;
	for (int i=0;i<m;i++)
		for (int j=0;j<=n;j++)
			for (int k=0;k<2;k++)
			if (f[i][j][k]){
				int x=f[i][j][k];
				if (j) (f[i+1][j-1][k||j==1]+=x)%=mo,(f[i+1][j][k||j==1]+=x)%=mo;
				if (j<n) (f[i+1][j][k]+=x)%=mo,(f[i+1][j+1][k]+=x)%=mo;
			}
	int ans=0;
	for (int i=0;i<=n;i++) (ans+=f[m][i][1])%=mo;
	printf("%d\n",ans);
}

Submission Info

Compile Error

./Main.cpp: In function ‘int main()’:
./Main.cpp:6:23: warning: ignoring return value of ‘int scanf(const char*, ...)’, declared with attribute warn_unused_result [-Wunused-result]
  scanf("%d%d\n",&n,&m);
                       ^

Judge Result