Submission #119305

---

Source Code Expand

#include<stdio.h>
#include<algorithm>
using namespace std;
int mod=1000000007;
struct wolf{
	long long d[3000];
	wolf(){
		for(int i=0;i<3000;i++)d[i]=0;
	}
};
int n,k;
wolf Div;
wolf solve(int a){
	if(a==0){
		wolf ret=wolf();
		ret.d[0]=1;
		return ret;
	}
	wolf p=solve(a/2);
	wolf ret=wolf();
	for(int i=0;i<k;i++){
		for(int j=0;j<k;j++){
			ret.d[i+j+(a&1)]=(ret.d[i+j+(a&1)]+p.d[i]*p.d[j]%mod)%mod;
		}
	}
	for(int i=2*k;i>=k;i--){
		int val=ret.d[i];
		for(int j=0;j<=k;j++){
			ret.d[i-j]=(ret.d[i-j]-Div.d[k-j]*val)%mod;
			if(ret.d[i-j]<0LL)ret.d[i-j]+=mod;
		}
	}
	//printf("%d:",a);
	//for(int i=0;i<k;i++)printf(" %d",ret.d[i]);
	//printf("\n");
	return ret;
}
int main(){
	scanf("%d%d",&k,&n);
	for(int i=0;i<k;i++){
		Div.d[i]=-1;
	}
	Div.d[k]=1;
	wolf D=solve(n-1);
	int ret=0;
	for(int i=0;i<k;i++)ret=(ret+D.d[i])%mod;
	printf("%d\n",ret);
}

Submission Info

Compile Error

./Main.cpp: In function ‘int main()’:
./Main.cpp:39:21: warning: ignoring return value of ‘int scanf(const char*, ...)’, declared with attribute warn_unused_result [-Wunused-result]

Judge Result