Answer in Java
Tim while preparing for his CAT exam, was studying the topic Number Systems. He encountered a loving da question:
Given a number N, find the number of pairs (cy) where both x and y are less than N and Highent Common Factor(HCF) of x and y is 1.
You have to solve the question for him.
Note: 0 can be included within the pairs
Input Specification:
Input: The number N from which the pairs (x,y) should be obtained
Output Specification:
Return the total number of pairs
Example 1:
input1: 4
Output: 9
Explanation:
The pairs can be (1,0) ,(0,1) (1,1) (1,2) (2,1) (0, 3) (3,1) (2,3) (0,2)
So, a total of 9 pairs