Submission #1051767

---

Source Code Expand

#include<cstdio>
#include<algorithm>
#include<cstring>
#include<iostream>
#include<vector>
#include<set>
#include<map>
#include<bitset>
#include<cmath>
#include<string>

#define ls (t<<1)
#define rs ((t<<1)+1)
#define mid ((l+r)>>1)
#define fi first
#define se second
#define mk make_pair
#define pb push_back

#define N 100005
#define M 200005
#define seed 23333
#define Mo 1000000007

using namespace std;
int i,j,m,n,p,k,a,b,c,ans,fac[N],inv[N];
int C(int x,int y)
{
		if (x<y) return 0;
		return 1ll*fac[x]*inv[y]%Mo*inv[x-y]%Mo;
}
int power(int x,int y)
{
		int s=1;
		for (;y;y>>=1)
		{
				if (y&1) s=1ll*s*x%Mo;
				x=1ll*x*x%Mo;
		}
		return s;
}
void jia(int &x,int y)
{
		x+=y; if (x>=Mo) x-=Mo;
}
int main()
{
	scanf("%d%d%d%d",&n,&a,&b,&c);
	fac[0]=inv[0]=1;
	for (i=1;i<N;++i) fac[i]=1ll*fac[i-1]*i%Mo,inv[i]=power(fac[i],Mo-2);
	if (b&1) puts("0");
	else 
	{
		  b/=2;
		  for (i=0;i<=a;++i)
		  	for (j=0;i+j<=c;++j)
		  		if ((c-i-j)%3==0)
		  		{
		  				jia(ans,1ll*C(a+b,a)*C(a,i)%Mo*C(b+j-1,j)%Mo*C(a+b+1+(c-i-j)/3-1,(c-i-j)/3)%Mo); 
		  		}
		printf("%d\n",ans);
	}
}

Submission Info

Compile Error

./Main.cpp: In function ‘int main()’:
./Main.cpp:48:31: warning: ignoring return value of ‘int scanf(const char*, ...)’, declared with attribute warn_unused_result [-Wunused-result]
  scanf("%d%d%d%d",&n,&a,&b,&c);
                               ^

Judge Result