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BJP3 Exercise 5.2: gcd

Language/Type: Java method basics mod while loops
Author: Leslie Ferguson (on 2013/04/01)

Write a method named gcd that accepts two integers as parameters and returns the greatest common divisor of the two numbers. The greatest common divisor (GCD) of two integers a and b is the largest integer that is a factor of both a and b. The GCD of any number and 1 is 1, and the GCD of any number and 0 is that number.

One efficient way to compute the GCD of two numbers is to use Euclid's algorithm, which states the following:

GCD(A, B) = GCD(B, A % B)
GCD(A, 0) = Absolute value of A

In other words, if you repeatedly mod A by B and then swap the two values, eventually B will store 0 and A will store the greatest common divisor.

For example: gcd(24, 84) returns 12, gcd(105, 45) returns 15, and gcd(0, 8) returns 8.

Type your solution here:


This is a method problem. Write a Java method as described. Do not write a complete program or class; just the method(s) above.

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