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:
- C Program for efficiently print all prime factors of a given number
- Java Program for efficiently print all prime factors of a given number
- C program to calculate the value of nPr
- Program to calculate value of nCr
- Program to calculate the value of nPr
- Program to Calculate e^x by Recursion
- Write a program to calculate pow(x,n)
- Program to calculate the value of sin(x) and cos(x) using Expansion
- Efficient program to calculate e^x
- Program to calculate Profit Or Loss
- Program to calculate the area of Kite
- Program to calculate distance between two points in 3 D
- Program to calculate Area Of Octagon
- Program to calculate distance between two points
- Program to calculate GST from original and net prices
If you like GeeksforGeeks and would like to contribute, you can also write an article using contribute.geeksforgeeks.org or mail your article to email@example.com. See your article appearing on the GeeksforGeeks main page and help other Geeks.
Please Improve this article if you find anything incorrect by clicking on the "Improve Article" button below.