Loops.java

import java.io.*;
import java.util.*;

public class Loops {
    
    private int ans, small;
    private boolean tf;

    public int fact(int n){
	if (n == 0)
	    return 1;
	else 
	    return n * fact(n - 1);
    }

    public int fact2(int n){
	ans = 1;
	while (n >= 1) {
	    ans = ans * n;
	    n = n - 1;
	}
	return ans;
    }

    public int gcd(int a, int b){
	small = a;
	if (a > b)
	    small = b;
	while (a%small != 0 || 
	       b%small != 0){
	    small = small - 1;
	}
	return small;
    }

    public int gcd2(int a, int b) {
	int remainder, sml, big;
	if (b>=a) {
	    remainder = b%a;
	    sml = a;
	    big = b;
	}
	else {
	    remainder = a%b;
	    sml = b;
	    big = a;
	}
	while (remainder != 0) {
	    remainder = sml % remainder;
	}
	return sml;
    }


    public boolean isPrime(int n) {
	int var = 2;
	tf=true;
	while (var < n){
	    if (n%var ==0) {
		tf=false;
	    }
	    var = var + 1;
	}
	return tf;
    }
}