spoj#ZSUM. Just Add It
Just Add It
For two given integers n and k find (Zn + Zn-1 - 2Zn-2) mod 10000007, where Zn = Sn + Pn and Sn = 1k + 2k + 3k + … + nk and Pn = 11 + 22 + 33 + … + nn.
Input
There are several test cases (≤ 10000). In each case two space separated positive integers n and k are given.
For last test case n and k are given as 0 0, which is not to be processed.
Constraints
1 < n < 200000000
0 < k < 1000000
Output
For each case print the asked value in separate line.
Example
Input: 10 3 9 31 83 17 5 2 0 0</p>Output: 4835897 2118762 2285275 3694