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permutations code found on the internet for bonfire challenge
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| function permAlone(str) { | |
| var permArr = [], usedChars = []; | |
| function permute(input) { | |
| //convert input into a char array (one element for each character) | |
| var i, ch, chars = input.split(""); | |
| for (i = 0; i < chars.length; i++) { | |
| //get and remove character at index "i" from char array | |
| ch = chars.splice(i, 1); | |
| //add removed character to the end of used characters | |
| usedChars.push(ch); | |
| //when there are no more characters left in char array to add, add used chars to list of permutations | |
| if (chars.length == 0) permArr[permArr.length] = usedChars.join(""); | |
| //send characters (minus the removed one from above) from char array to be permuted | |
| permute(chars.join("")); | |
| //add removed character back into char array in original position | |
| chars.splice(i, 0, ch); | |
| //remove the last character used off the end of used characters array | |
| usedChars.pop(); | |
| } | |
| return permArr; | |
| } | |
| permArr = permute(str); | |
| // filter out duplicates from permArr | |
| permArr = permArr.filter(function(perm, index) { | |
| perm = perm.split(''); | |
| return perm.every(function(letter, index) { | |
| if (index === perm.length-1) { | |
| return true; | |
| } | |
| return (letter !== perm[index+1]); | |
| }); | |
| }); | |
| return permArr.length; | |
| } | |
| permAlone('baa'); |
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