import java.io.*;
import java.util.*;
public class GCD {
public int GCD(int a, int b) {
int n;
if (a<b) {
n=a;
while (n!=0) {
if (b%n==0 && a%n==0) {
return n;
}
else {
n=n-1;
}
}
return 1;
}
else{
n=b;
while (n!=0) {
if (b%n==0 && a%n==0) {
return n;
}
else {
n=n-1;
}
}
return 1;
}
}
public int GCD2(int a, int b){
if (b==0){
return a;
}
else if (a==0) {
return b;
}
else {
while (a!=b) {
if (a>b){
a=a-b;
}
else {b=b-a;}
}
}
return a;
} /* there is no obvious speed difference between the two gcd functions */
public boolean isPrime(int n){
int q=2;
while (q<n){
if (n%q == 0) {
return false;
}
else {
q=q+1;
}
}
return true;
}
}