Matrix Multiplication Template

//link : https://codeforces.com/contest/1117/submission/50110620
#include<bits/stdc++.h>
using namespace std;

#define ll long long

const int SIZE=105;
const int mod=(int)1e9+7;

struct Mat{
    ll v[SIZE][SIZE];
    Mat(){
        memset(v,0,sizeof(v));
    }
};

Mat mulmat(Mat &a,Mat &b,int n=SIZE)
{
    Mat ret;
    int i,j,k;
    for(i=1;i<=n;i++){
        for(j=1;j<=n;j++){
            for(k=1;k<=n;k++){
                ret.v[i][j]=(ret.v[i][j]+(a.v[i][k]*b.v[k][j])%mod)%mod;
            }
        }
    }
    return ret;

}

Mat powmat(Mat a,ll p,int n=SIZE)
{
    Mat ret;
    for(int i=1;i<=n;i++)ret.v[i][i]=1;
    while(p){
        if(p%2)ret=mulmat(ret,a,n);
        a=mulmat(a,a,n);
        p>>=1;
    }
    return ret;
}

void print(Mat a,int n=SIZE)
{
    for(int i=1;i<=n;i++){
        for(int j=1;j<=n;j++)
            cout<<a.v[i][j]<<' ';
        cout<<endl;
    }
}

int main()
{
    ll n=3,k=2;
    int i,j;
    cin>>n>>k;
    if(n<k)return cout<<1<<endl,0;

    Mat now;
    for(i=1;i<k;i++)now.v[i][i+1]=1;
    now.v[1][1]=now.v[k][1]=1;

    now=powmat(now,n-k+1,k);
    //print(now,k);
    ll ans=0;
    for(i=1;i<=k;i++)ans=(ans+now.v[i][1])%mod;

    cout<<ans<<endl;
}