find the greatest common divisor

Given the value of two integers a, b, r represents the number remaining after the modulo. If a%b==0, directly output b as the greatest common divisor; if a%b!=0, enter the loop, and keep taking the modulo for the remainder until a%b==0.

For example: a = 24,b = 32;

r = a%b =24; (r!=0 enters the loop)

a = 32, b = 24;

r = a%b = 8 ; (r!=0 enters the loop)

a = 24,b = 8;

r = a%b =0; (r==0 to jump out of the loop)

Output greatest common divisor: 8

code show as below:

#include <stdio.h>
intmain()
{
	int a = 24;
	int b = 32;
	int r = 0;
	while ((r = a%b) != 0)
	{
		a = b;
		b = r;
	}
	printf("The greatest common divisor is: %d\n", b);
	return 0;
}

Supplement: least common multiple * greatest common divisor = product of two numbers

Therefore, the least common multiple can be solved by the above formula.

code show as below:

#include <stdio.h>
intmain()
{
	int a = 24;
	int b = 32;
	int tmp = a*b;
	int r = 0;
	while ((r = a%b) != 0)
	{
		a = b;
		b = r;
	}
	printf("The greatest common divisor is: %d\n", b);
	printf("The least common multiple is: %d\n",tmp/b );

	return 0;
}