Free Code Camp Bonfire 4 and 5

[madbernard]

So, 4 was trivial, which was great: make a function that factorializes numbers. Like, 5! is 1 * 2 * 3 * 4 * 5 = 120.

function factorialize(num) {
for (var i = (num - 1); i > 0; i--) {
num *= i;
}
return num;
}

factorialize(5);

But 5... I feel like I shouldn't have to make my own function that takes an array and jams it all into a single string without commas separating the bits. But the concat stuff I was looking at in the Mozilla Developer Network wasn't working that way (even though their example shows it should. So baffled).

And I feel like there must be some way to not declare like 7 variables... But I couldn't figure out how to chain these methods/functions. Anyway: here it is, a function that checks if a statement is a palindrome (ignoring all the non-letter things! The RegEx stuff was honestly fun learning).

function reverseString(str) {
var reverseStr = '';
for (var i = str.length - 1; i > -1; i--){
reverseStr += str[i];
}
return reverseStr;
}

function arrToRevStr(arr) {
var str = '';
for (var i = arr.length - 1; i > -1; i--){
str += arr[i];
}
return str;
}

function palindrome(str) {
var cleanStrArray = /(\w)/g.exec(str);
var cleanStr = arrToRevStr(cleanStrArray);
var cleanStrLow = cleanStr.toLowerCase();

var reverseStr = reverseString(str);
var cleanReverseStrArray = /(\w)/g.exec(reverseStr);
var cleanReverseStr = arrToRevStr(cleanReverseStrArray);
var cleanReverseStrLow = cleanReverseStr.toLowerCase();

if (cleanStrLow == cleanReverseStrLow) {return true;}
else {return false;}
}

palindrome("eye");