#P10973. [2015杭电多校]Convex Polygon
[2015杭电多校]Convex Polygon
Convex Polygon
Problem Description
Cute qzy wants to calculate how many convex polygons with M vertices and K acute angles when selecting M vertices in a regular polygon with N vertices(N is odd).But he is busy with girls,so he asks you for help.Can you solve it?
Input
The first line contains a number T, indicating the number of test cases.(T≤50000) For each case, there are three numbers N(3≤N≤100000), M(3≤M≤N), K(0≤K≤M), as described previously.
Output
For each case, print the Case #d: answer mod 1000000007 in each line.
Sample Input
1
5 4 2
Sample Output
Case #1: 5
Hint

Author
UESTC
Source
2015 Multi-University Training Contest 7