A shop has n identical gumballs and k distinct labeled jars in a row. Count the number of ways to place all n gumballs into the jars, where any jar may hold from zero up to all of the gumballs. Two placements differ if some jar ends up with a different number of gumballs. Report the count modulo 1000000007.
Input format
A single line with two integers n and k.
Output format
A single integer: the number of distributions, modulo 1000000007.
Constraints
- 0 <= n <= 1000
- 1 <= k <= 1000