import java.util.Scanner;

public class GreatestCommonDivisor {

public static void main(String[] args) {

// -----------------------Method 1----------------------------

// System.out.println(getGreatestCommonDivisor(15,20));

// }public static int getGreatestCommonDivisor(int first, int second){

// if(first<10 || second<10){

// return -1;

// }

//

// while(first!=second){

//

// if(first>second){

// first=first-second;

// }

// else{

// second=second-first;

// }

// }

// return second;

// ------------------------Method 2---------------------------

Scanner scanner=new Scanner(System.in);

System.out.print("Enter two Positive integers: ");

int num1=scanner.nextInt();

int num2=scanner.nextInt();

scanner.close();

int greatestCommonDivisor=1;

for(int i=1; i<=num1 && i<=num2; i++) {

if(num1%i==0 && num2%i==0) {

greatestCommonDivisor=i;

}

}

System.out.println("Greatest Common Divisor of "+num1+" and "+num2+" = "+greatestCommonDivisor);

}

}