Quite recently a creative student Lesha had a lecture on trees. After the lecture Lesha was inspired and came up with the tree of his own which he called a *k*-tree.

A *k*-tree is an infinite rooted tree where:
 -  each vertex has exactly *k* children; -  each edge has some weight; -  if we look at the edges that goes from some vertex to its children (exactly *k* edges), then their weights will equal 1, 2, 3, ..., *k*. 
The picture below shows a part of a 3-tree.

 

 <img class="tex-graphics" src="https://espresso.codeforces.com/61ac5ac17c4d2f220968eff8fb59bb3c8dc77edf.png" style="max-width: 100.0%;max-height: 100.0%;"/>

 

Help Dima find an answer to his question. As the number of ways can be rather large, print it modulo 1000000007 (10<sup class="upper-index">9</sup> + 7).
A single line contains three space-separated integers: *n*, *k* and *d* (1 ≤ *n*, *k* ≤ 100; 1 ≤ *d* ≤ *k*).
#include <bits/stdc++.h>
#define int long long
using namespace std;

signed path(int n,int k,int ans){
    if(n<=1){
        //cout<<n<<endl;
        return 1;
        
    }
    for(int i=0;i<k;i++){
        
        //cout<<path(n-i-1,k,0)<<endl;
        if(i+1<=n){
            ans+=path(n-i-1,k,0);
            //cout<<i<<endl;
        }
        
    }
    return ans;

}

signed main(){
    int n,k,d;
    cin>>n>>k>>d;
    cout<<path(n,k,0)-path(n,d-1,0)<<endl;
    return 0;

}