Bharat was given a problem to solve, by his brother, Lord Ram. The problem was like, given integers, $N$ and $K$, Bharat has to find the number (possibilities) of non-increasing arrays of length $K$, where each element of the array is between $1$ and $N$ (both inclusive). He was confused, regarding this problem. So, help him solve the problem, so that, he can give the answer of the problem, to his brother, Lord Rama. Since, the number of possible sub-arrays can be large, Bharat has to answer the problem as "number of possible non-increasing arrays", modulo $10^9$ $+$ $7$.

-----Input:-----
- Two space-seperated integers, $N$ and $K$.

-----Output:-----
- Output in a single line, the number of possible non-increasing arrays, modulo $10^9$ $+$ $7$.

-----Constraints:-----
- $1 \leq N, K \leq 2000$

-----Sample Input:-----
2 5

-----Sample Output:-----
6

-----Explanation:-----
- Possible Arrays, for the "Sample Case" are as follows:
- {1, 1, 1, 1, 1}
- {2, 1, 1, 1, 1}
- {2, 2, 1, 1, 1}
- {2, 2, 2, 1, 1}
- {2, 2, 2, 2, 1}
- {2, 2, 2, 2, 2}
- Hence, the answer to the "Sample Case" is $6$ ($6$ % ($10^9$ $+$ $7$)).

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