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@pReya pReya/palindrome.js
Last active Oct 22, 2017

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Simple node.js palindrome checker for the command line.
const readline = require('readline');
const rl = readline.createInterface({
input: process.stdin,
output: process.stdout
});
rl.question('Please enter potential palindrome: ', checkForPalindrome);
function checkForPalindrome(str)
{
var resultText = "";
// Only allow upper and lower case letters
if (/^[a-zA-Z]+$/.test(str))
{
var result = true;
resultText = "\"" + str + "\"" + " is a palindrome!";
var strLowerCase = str.toLowerCase();
for (var i = 0; i < str.length/2; i++)
{
var currentLetterLeft = strLowerCase[i];
// Remember to substract 1 from length because of zero-indexing strings
var currentLetterRight = strLowerCase[str.length-1-i];
if (currentLetterLeft != currentLetterRight)
{
result = false;
resultText = "\"" + str + "\"" + " is NOT a palindrome!";
break;
}
}
}
else
{
resultText = "Only upper and lower case letters are allowed!";
}
console.log(resultText);
rl.close();
}
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