Virtual contest is a way to take part in past contest, as close as possible to participation on time. It is supported only ACM-ICPC mode for virtual contests.
If you've seen these problems, a virtual contest is not for you - solve these problems in the archive.
If you just want to solve some problem from a contest, a virtual contest is not for you - solve this problem in the archive.
Never use someone else's code, read the tutorials or communicate with other person during a virtual contest.

No tag edit access

C. k-Tree

time limit per test

1 secondmemory limit per test

256 megabytesinput

standard inputoutput

standard outputQuite 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.

Help Dima find an answer to his question. As the number of ways can be rather large, print it modulo 1000000007 (10^{9} + 7).

Input

A single line contains three space-separated integers: *n*, *k* and *d* (1 ≤ *n*, *k* ≤ 100; 1 ≤ *d* ≤ *k*).

Output

Print a single integer — the answer to the problem modulo 1000000007 (10^{9} + 7).

Examples

Input

3 3 2

Output

3

Input

3 3 3

Output

1

Input

4 3 2

Output

6

Input

4 5 2

Output

7

Codeforces (c) Copyright 2010-2017 Mike Mirzayanov

The only programming contests Web 2.0 platform

Server time: Apr/27/2017 02:23:43 (c3).

Desktop version, switch to mobile version.
User lists

Name |
---|