4027: The World is a Theatre
[Creator : ]
Description
time limit per test
2 secondsmemory limit per test
256 megabytesinput
standard inputoutput
standard outputThere are n boys and m girls attending a theatre club. To set a play "The Big Bang Theory", they need to choose a group containing exactly t actors containing no less than 4 boys and no less than one girl. How many ways are there to choose a group? Of course, the variants that only differ in the composition of the troupe are considered different.
Perform all calculations in the 64-bit type: long long for C/C++, int64 for Delphi and long for Java.
Input
The only line of the input data contains three integers n, m, t (4≤n≤30,1≤m≤30,5≤t≤n+m).
Output
Find the required number of ways.
Please do not use the %lld specificator to read or write 64-bit integers in C++. It is preferred to use cin, cout streams or the %I64d specificator.
Examples
Input
5 2 5
Output
10
Input
4 3 5
Output
3