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caesarCipher.js
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caesarCipher.js
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function caesarCipher(s, k) {
const alphabet = ("abcdefghijklmnopqrstuvwxyz").split('')
const stringArr = s.split('')
let rotatedString = ""
for(let i = 0; i < stringArr.length; i++) {
let char = stringArr[i]
const isUpperCase = char === char.toUpperCase()
char = char.toLowerCase()
if(alphabet.includes(char)) {
const charIndexInAlphabet = alphabet.findIndex(ch => ch === char)
let rotatedChar = ""
if(charIndexInAlphabet + k >= alphabet.length) {
const j = (charIndexInAlphabet + k) % alphabet.length
rotatedChar = alphabet[j]
} else {
rotatedChar = alphabet[charIndexInAlphabet + k]
}
rotatedString += isUpperCase ? rotatedChar.toUpperCase() : rotatedChar
} else {
rotatedString = rotatedString.concat(char);
}
}
return rotatedString;
}
// Option 2 //
function caesarCipher(s, k) {
const alphabet = "abcdefghijklmnopqrstuvwxyz";
const alphabetLength = alphabet.length;
k = k % alphabetLength;
let result = "";
for (let i = 0; i < s.length; i++) {
let char = s[i];
let isMayus = char === char.toUpperCase();
char = char.toLowerCase();
if (alphabet.includes(char)) {
let currentIndex = alphabet.indexOf(char);
let newIndex = (currentIndex + k) % alphabetLength;
let newChar = alphabet[newIndex];
result += isMayus ? newChar.toUpperCase() : newChar;
} else {
result += s[i];
}
}
return result;
};