Cesar's Cipher - Cant get punctuation right

JavaScript
#1

Tell us what’s happening:
Everything else is being decoded, but I cant seem to get the punctation to carry over. Not sure if my regex is setup right or even valid.

Please help. Much appreciated!!

BD

Your code so far


function rot13(str) {
///establish alphabet or rule
let alpha = "ABCDEFGHIJKLMNOPQRSTUVWXYZ"
let alphArr = alpha.split('')


//split given string into array
let strArr = str.split("")
console.log("original string: " + strArr)
console.log(typeof strArr[4])
let newArr = []



// for each letter in the given string. find its position /index on the alphabet or rule thenr educe that position by 13.

for (let i = 0; i <= strArr.length; i++){

if (strArr[i] === ' ')
{newArr.push(" ")}

else if (strArr[i] === /A-Za-z0-9_/g) {newArr.push(strArr[i])}

else if (typeof strArr[i] === 'string' && alphArr.indexOf(strArr[i]) >= 13) {newArr.push(alphArr[alphArr.indexOf(strArr[i]) - 13])}

else if (typeof strArr[i] === 'string' && alphArr.indexOf (strArr[i]) < 13){newArr.push(alphArr[alphArr.indexOf(strArr[i]) + 13])}


}

console.log(newArr.join(""))

return newArr.join("");
}

rot13("SERR PBQR PNZC");

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Challenge: Caesars Cipher

Link to the challenge:

#2

I dont remember regexp could be used like that, try using str.test(regexp)

#3

the condition you use with regex checks if the left value is strictly equal to regular expression (===) . Like someone before me suggested, you should use the test method

#4

this is always false

there is no index strArr.length, if you use that index to get a value you get undefined

the punctuation returns true for this, as indexOf will return -1

1 Like
#5

Hi!
1.
For the special characters “!”, “?” and “.” I have added the following instruction to your code and it works:

else if (strArr[i] == "!" | strArr[i] == "." | strArr[i] == "?") {newArr.push(strArr[i]);}

That also will work!

let reg = /[!?.]$/
.......
.......
else if (reg.test(strArr[i]) == true) {newArr.push(strArr[i];
1 Like
#6

Thank you for the feedback!

#7

Hi Moriel!

Thank you for your great help with this. It worked like a charm. Much appreciated!

BD

1 Like
#8

Thank you for your help with this! Much appreciated.

#9

Thank you Sylvant! I got it sorted.