Javascript Interview Question String Check Palindrome

Introduction

A Palindrome is a word, phrase, or sequence that reads the same backward as forward

Given an input string, return true if it is a Palindrome, false if it isn't

Examples: 

isPalindrom('Never odd or even') should return true
isPalindrom('You are a special snowflake') should return false 

function isPalindrom (string) {

}
/*  Do not edit below this line */

var line = '***********************************************************************';
var passed = 0;/*from w ww . j a  va2s .  com*/
var failed = 0;

console.log(line);
console.log('isPalindrom UNIT TESTS');
console.log(line);

if (isPalindrom('rotator') === true) {
    console.log("Test 1 pass, isPalindrom('rotator') returns true");
    passed += 1;
} else {
    console.log("Test 1 failed, isPalindrom('rotator') should return true");
    failed += 1;
}

if (isPalindrom('You are a special snowflake') === false) {
    console.log("Test 2 pass, isPalindrom('You are a special snowflake') returns false");
    passed += 1;
} else {
    console.log("Test 2 failed, isPalindrom('You are a special snowflake') should return false");
    failed += 1;
}

if (isPalindrom('Never odd or even') === true) {
    console.log("Test 3 pass, isPalindrom('Never odd or even') returns true");
    passed += 1;
} else {
    console.log("Test 3 failed, isPalindrom('Never odd or even') should return true");
    failed += 1;
}

console.log(line);
console.log('TOTAL TESTS PASSED: ' + passed );
console.log('TOTAL TESTS FAILED: ' + failed );
console.log(line);



function isPalindrom(string) {
    var alphabet = 'abcdefghijklmnopqrstuvwxyz';
    var char = '';
    var parsedString = '';
    var reverseString = '';

    for (var i = 0; i < string.length; i += 1) {
        // Palindroms are not case sensitive, 
        //so we make all letters lower case before we evaluate them
        char = string[i].toLowerCase();
        // We only want to add letters to our parsedString and reverseString
        if (alphabet.indexOf(char) > -1) {
            parsedString = parsedString + char;
            reverseString = char + reverseString;
        }
    }

    return parsedString === reverseString;
}
/*  Do not edit below this line */

var line = '***********************************************************************';
var passed = 0;
var failed = 0;

console.log(line);
console.log('isPalindrom UNIT TESTS');
console.log(line);

if (isPalindrom('rotator') === true) {
    console.log("Test 1 pass, isPalindrom('rotator') returns true");
    passed += 1;
} else {
    console.log("Test 1 failed, isPalindrom('rotator') should return true");
    failed += 1;
}

if (isPalindrom('You are a special snowflake') === false) {
    console.log("Test 2 pass, isPalindrom('You are a special snowflake') returns false");
    passed += 1;
} else {
    console.log("Test 2 failed, isPalindrom('You are a special snowflake') should return false");
    failed += 1;
}

if (isPalindrom('Never odd or even') === true) {
    console.log("Test 3 pass, isPalindrom('Never odd or even') returns true");
    passed += 1;
} else {
    console.log("Test 3 failed, isPalindrom('Never odd or even') should return true");
    failed += 1;
}

console.log(line);
console.log('TOTAL TESTS PASSED: ' + passed );
console.log('TOTAL TESTS FAILED: ' + failed );
console.log(line);



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