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*).
def main():
    MOD = 1_000_000_007
    n, k, d = read_ints()

    def solve(n, k, atleast_cond=False):
        if n == 0 and atleast_cond:
            return 1

        if n < 0:
            return 0

        res = 0
        for ki in range(1, k+1):
            res += solve(n-ki, k, atleast_cond or ki >= d)
            res %= MOD

        return res

    ans = solve(n, k)
    print(ans)


def input(): return next(test).strip()
def read_ints(): return [int(c) for c in input().split()]
def print_lines(lst): print('\n'.join(map(str, lst)))


if __name__ == "__main__":
    import sys
    from os import environ as env
    if 'COMPUTERNAME' in env and 'L2A6HRI' in env['COMPUTERNAME']:
        sys.stdout = open('out.txt', 'w')
        sys.stdin = open('in.txt', 'r')

    test = iter(sys.stdin.readlines())

    main()
