/*
	JavaScript H.C.F program by lolman_ks.
    Logic is very nicely explained throught comments in the code.
*/

function gcd(){
    if(arguments.length == 0) return 1;
	if(arguments.length == 1) return arguments[0];

	var common_factors = [];
	var counter_1 = 1; //For testing different numbers as GCD.
	var counter_2 = 0; //For looping through arguments.

	//Loop for testing different numbers from 1 to minimum from arguments.
	while((counter_1 <= Math.min.apply(null , arguments))){
		//Check for exact divisibility of arguments[counter_2] by counter_1.
		if(arguments[counter_2] % counter_1 == 0){
			++counter_2; //Move to the next item in the array.
		}
		//If not exactly divisible.
		else{
			++counter_1; //Test the next number to be tested as GCD.
			counter_2 = 0; //Move to the first element of arguments.
		}
		/*
			counter_2 will be == arguments.length, if its value is not
			reset and the first condition is true for each element of 
			the array.
			Therefore, the number will be a common factor.
		*/
		if(counter_2 == arguments.length){
			common_factors.push(counter_1); //Add counter_1 to common_factors array.
		}
	}
	return Math.max.apply(null , common_factors);
}

/*
	I hope my answers are useful  to you, please promote them if they are.
    #lolman_ks.
*/