CodeWar Challenges

Advanced PigLatin.js

function translate(sentence) {
  const vowels = 'aeiou'.split('');
  
  const isUpper = (char => char === char.toUpperCase());
  
  const pigLatin = ((str, i = 0) => {
    if (vowels.includes(str[0])) {      
      return i === 0 ? str + 'way' : str + 'ay';
    }
    
    return pigLatin(str.slice(1) + str.slice(0, 1), i + 1);
  });
  
  return sentence
    .split(' ')
    .map(word => {
      let puncs = word.match(/\W/g);
      if (puncs) puncs = puncs.join('');
      if (puncs) plen = puncs.length;
      else {
        plen = 0;
        puncs = '';
      }
      
      let latin = pigLatin(word.toLowerCase().slice(0, word.length - plen)) + puncs;
      if (isUpper(word[0])) latin = latin[0].toUpperCase() + latin.slice(1);
      return latin;
    }).join(' ');
};

Coordinates Validator.js

function isValidCoordinates(coord){
  let [lat, lon, ...rest] = coord
    .replace('e','ex')
    .split(',')
    .map(Number);
  
  if (rest.length > 0) return false;
  
  if (lat > 90 || lat < -90) return false;
  if (lon > 180 || lon < -180) return false;
  
  if (isNaN(lat) || isNaN(lon)) {
    return false;
  }
  
  return true;
  
}

Formatting a number as price.js

var numberToPrice = function(number) {
  if (!Number.isFinite(number)) {
    return 'NaN';
  }
  
  number = number.toLocaleString();
  
  let [num, dec] = number.split('.');
  
  if (dec) {
    if (dec.length === 1) {
    dec = dec + '0';
    }
    dec = dec.slice(0, 2);
  } else {
    dec = '00';
  }
  
  return num + '.' + dec;
}

integers-recreation-one.js

function listSquared(m, n) {
  let rootDivisors = [];
  
  for (let i = m; i <= n; i++) {
    let divisors = [];
    
    for (let j = 1; j <= i; j++) {
      // Push every divisor of numbers...
      if (i % j === 0) divisors.push(j);
    }
    
    let divisorsSquared = divisors.map(x => x * x);
    
    let sumOfDivisorsSquared = divisorsSquared.reduce((a, b) => a + b);
    
    if (Number.isInteger(Math.sqrt(sumOfDivisorsSquared))) {
      rootDivisors.push([i, sumOfDivisorsSquared]);
    }
  }
  
  return rootDivisors;
}

Mod4 Regex.js

var Mod4 = /(^(.*)?\[(\+|\-)?(\d+)?(00|04|08|12|16|20|24|28|32|36|40|44|48|52|56|60|64|68|72|76|80|84|88|92|96)\](.*)?$)|(^(.*)?\[(\+|\-)?(0|4|8)\](.*)?$)/

palindrome-chain-length.js

var palindromeChainLength = function(n) {
  let isPalindrome = x => x.toString().split('').reverse().join('') == x;
  
  if (isPalindrome(n)) {
    return 0;
  }
  
  let steps = 0;
  
  while (!isPalindrome(n)) {
    n = n + Number(n.toString().split('').reverse().join(''));
    steps++;
  }
  
  return steps;
};

rgb-to-hex.js

function rgb(r, g, b){
  /** 
    if x is greater than 0:
      - if x is greater than 255:
        x is 255 else 0
    else x is 0;
  **/
  const sanitize = x => x > 0 ? (x > 255 ? 255 : x) : 0;
  
  r = sanitize(r).toString(16);
  g = sanitize(g).toString(16);
  b = sanitize(b).toString(16);
  
  const pad = x => (x.length < 2) ? (0 + x) : x;
  
  return (pad(r) + pad(g) + pad(b)).toUpperCase();
}

strip-url-params.js

function stripUrlParams(url, paramsToStrip = []){
  let slug = '', 
      URL = url.split('?')[0], 
      params = url.split(/\?|&/).slice(1);

  params.reduce((acc, cur, i) => {
    let [data, value] = cur.split('=');  

    if (!acc[data] && !paramsToStrip.includes(data)) {
      acc[data] = value;
      (i === 0) ? slug += `?${data}=${value}` : slug += `&${data}=${value}`;
    }

    return acc;
  }, {});

  return  URL + slug;
}

sum-string.js

function sumStrings(a, b) {
  let m = a.split('').reverse();
  let n = b.split('').reverse();
  
  let ans = ''; let rem = 0;
  
  for (let i = 0; i < Math.max(a.length, b.length); i++) {
    
    let s = (m[i] ? +m[i] : 0) + (n[i] ? +n[i] : 0);
    
    if (rem !== 0) {
     s += rem;
     rem = 0;
    }
    
    if (s < 10) {
     ans += s;
    } else {
     ans += +(s.toString()[1]);
     rem = +(s.toString()[0]);
    }
  }
  
  if (rem === 0) {
   rem = '';
  }
  
  ans = rem + ans.split('').reverse().join('');
  
    if (ans.length < 20) {
    ans = Number(ans).toString();
  }
  
  return ans;
}

the-hashtag-generator.js

function generateHashtag (str) {
  let hashedString = '#';
  
  if (str.length === 0 || str.length > 140) return false;
  
  for (let word of str.split(' ')) {
    hashedString += word.charAt(0).toUpperCase() + word.slice(1);
  }
  
  return hashedString;
}

valid-braces.js

function validBraces(braces){

  do {
    braces = braces.replace(/\(\)|\[\]|\{\}/, '');
  } while (/\(\)|\[\]|\{\}/.test(braces));
  
  return braces.length === 0;
}

Vigenère Cipher Helper.js

function VigenèreCipher(key, abc) {
  this.encode = function (str) {
    return str
        .split('')
        .map((c, i) => {
         return abc.includes(c) ? abc[(abc.indexOf(c) + abc.indexOf(key[i % key.length])) % abc.length] : c
        }).join('');
  };
  
  this.decode = function (str) {
    return str
        .split('')
        .map((c, i) => {
          let pos = (abc.indexOf(c) - abc.indexOf(key[i % key.length]));
          return abc.includes(c) ? (pos < 0 ? abc[abc.length - (~pos + 1)] : abc[pos])  : c
        }).join('');
  };
}