Given two numbers n, r ( n>=r ). The task is to find the value of C(n, r) for big value of n.
Input: n = 30, r = 15 Output: 155117520 C(30, 15) is 155117520 by 30!/((30-15)!*15!) Input: n = 50, r = 25 Output: 126410606437752
Approach: A simple code can be created with the following knowledge that :
C(n, r) = [n * (n-1) * .... * (n-r+1)] / [r * (r-1) * .... * 1]
However, for big values of n, r the products may overflow, hence during each iteration we divide the current variables holding value of products by their gcd.
Below is the required implementation:
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