Submission #1814248

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Source Code Expand

#include<cstdio>

const int MOD=1e9+7;
struct mint{int x;mint(int x=0):x(x){}};
inline mint operator+  (mint a,mint b){return a.x+b.x<MOD?a.x+b.x:a.x+b.x-MOD;}
inline mint operator-  (mint a){return MOD-a.x;}
inline mint operator-  (mint a,mint b){return a+-b;}
inline mint operator*  (mint a,mint b){return 1LL*a.x*b.x%MOD;}
inline mint operator<< (mint x,int y){mint r=1;for(;y;y>>=1,x=x*x)if(y&1)r=r*x;return r;}
inline mint operator~  (mint x){return x<<MOD-2;}
inline mint operator/  (mint a,mint b){return a*~b;}
inline mint&operator+= (mint&a,mint b){return a=a+b;}
inline mint&operator-= (mint&a,mint b){return a=a-b;}
inline mint&operator*= (mint&a,mint b){return a=a*b;}
inline mint&operator<<=(mint&x,int y){return x=x<<y;}
inline mint&operator/= (mint&a,mint b){return a=a/b;}

#define MN 3000
mint f[MN+5][MN+5],ff[MN+5][MN+5],ans;
int main()
{
	int n,m,i,j;
	scanf("%d%d",&n,&m);--m;
	for(i=1;i<=n;++i)f[0][i]=1;
	for(i=1;i<n;++i)ff[0][i]=1;
	for(i=0;i<m;++i)for(j=1;j<=n;++j)
	{
		f[i+1][j]+=f[i][j]+f[i][j];
		f[i+1][j-1]+=f[i][j];
		if(j<n)f[i+1][j+1]+=f[i][j];
		ff[i+1][j]+=ff[i][j]+ff[i][j];
		ff[i+1][j-1]+=ff[i][j];
		if(j+1<n)ff[i+1][j+1]+=ff[i][j];
	}
	for(i=1;i<=n;++i)ans+=f[m][i]-ff[m][i];
	printf("%d",4*ans);
}

Submission Info

Compile Error

./Main.cpp: In function ‘int main()’:
./Main.cpp:36:19: warning: format ‘%d’ expects argument of type ‘int’, but argument 2 has type ‘mint’ [-Wformat=]
  printf("%d",4*ans);
                   ^
./Main.cpp:23:21: warning: ignoring return value of ‘int scanf(const char*, ...)’, declared with attribute warn_unused_result [-Wunused-result]
  scanf("%d%d",&n,&m);--m;
                     ^

Judge Result