Problem:
Greatest Common Divisor

Write a program which finds the greatest common divisor of two natural numbers a and b

Input

a and b are given in a line sparated by a single space.

Output

Output the greatest common divisor of a and b.

Constrants

1 ≤ a, b ≤ 109

Hint

You can use the following observation:

For integers x and y, if x ≥ y, then gcd(x, y) = gcd(y, x%y)

Sample Input 1

54 20

Sample Output 1

2

Sample Input 2

147 105

Sample Output 2

21

Solution in C (judge verdict: Time Limit Exceeded)

#include<stdio.h>

int main()
{
	int x,y;
	int z;
	int amari;
	int ans;
	int c=0;


	scanf("%d",&x);
	scanf("%d",&y);

	if(x<=y)
	{
		z=x;
		x=y;
		y=z;
	}

	amari=x%y;
    while(c<=y)
    {
    	c++;
	        if(amari%c==0 && y%c==0)
	        {
	        	ans=c;
	        }

    }

printf("%d\n",ans);

}