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#include<cstdio>
#include<cstring>
#include<algorithm>
#include<iostream>
#include<queue>
#include<map>
#include<stack>
#include<cmath>
#include<set>
#include<bitset>
#include<assert.h>
#define inc(i,l,r) for(int i=l;i<=r;i++)
#define dec(i,l,r) for(int i=l;i>=r;i--)
#define link(x) for(edge *j=h[x];j;j=j->next)
#define mem(a) memset(a,0,sizeof(a))
#define ll long long
#define eps 1e-6
#define succ(x) (1<<x)
#define lowbit(x) (x&(-x))
#define sqr(x) ((x)*(x))
#define mid (x+y)/2
#define NM 105
#define nm 170005
#define pi 3.1415926535897931
const ll inf=1e9+7;
using namespace std;
ll read(){
ll x=0,f=1;char ch=getchar();
while(!isdigit(ch)){if(ch=='-')f=-1;ch=getchar();}
while(isdigit(ch))x=x*10+ch-'0',ch=getchar();
return f*x;
}
ll n,m;
struct mat{int n,m;ll a[NM][NM];}null,ans,t;
mat operator*(const mat&x,const mat&y){
mat s;s.n=x.n;s.m=y.m;mem(s.a);
inc(i,1,s.n)inc(j,1,s.m)inc(k,1,x.m)(s.a[i][j]+=x.a[i][k]*y.a[k][j]%inf)%=inf;
return s;
}
mat qpow(mat x,ll t){return t?qpow(sqr(x),t>>1)*(t&1?x:null):null;}
int main(){
n=read();m=read();
ans.n=m;ans.m=1;
inc(i,1,m)ans.a[i][1]=1;
t.n=t.m=m;
inc(i,1,m-1)t.a[i][i+1]=1;
t.a[m][1]=t.a[m][m]=1;
null.n=null.m=m;
inc(i,1,m)null.a[i][i]=1;
if(n>=m)ans=qpow(t,n-m+1)*ans;
printf("%lld\n",ans.a[m][1]);
return 0;
}
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