JavaScript Anagram

anagrams.js

// Tell if given strings are anagrams without using any API methods except split

function anagrams(str1, str2) {
  str1 = str1.split("");
  str2 = str2.split("");
  
  var charLen = [];
  var anagram = false;
  
  if(str1.length !== str2.length) {
    anagram = false;
    return console.log("Not an anagram");
  }
  for(var i=0; i<str1.length; i++) {
    if(!charLen[str1[i]]) {
      charLen[str1[i]] = 1;
    } else {
      charLen[str1[i]]++;
    }
  }
  for(var j=0; j<str2.length; j++) {
      charLen[str2[j]]--;
  }
  for(var k in charLen) {
    if(charLen[k] === 0) {
      anagram = true;
    } else {
      anagram = false;
      return console.log("Not an anagram");
    }
  }
  if(anagram) {
    return console.log("An anagram");
  }
}


/// Another implementation

function areAnagrams(str1, str2) {
  var hashMap = {};
  if (str1.length !== str2.length) {
    return false;
  }
  for(var i=0; i<str1.length; i++) {
    if(!hashMap[str1[i]]) {
      hashMap[str1[i]] = 1;
    } else {
      hashMap[str1[i]]++;
    }
  }
  for(var j=0; j<str2.length; j++) {
    if (hashMap[str2[j]]) {
      hashMap[str2[j]]--;
    }
  }
  Object.keys(hashMap).forEach(function(key){
    if (hashMap[key]) {
      return false; 
    }
  });
  return true;
}

//  Another implementation

function areAnagrams(str1, str2) {
  var hashMap = {};
  if (str1.length !== str2.length) {
    return false;
  }
  for(var i=0; i<str1.length; i++) {
    if(!hashMap[str1[i]]) {
      hashMap[str1[i]] = 1;
    } else {
      hashMap[str1[i]]++;
    }
  }
  for(var j=0; j<str2.length; j++) {
    if (--hashMap[str2[j]] < 0) {
      console.log(hashMap[str2[j]]);
      return false;
    }
  }
  return true;
}

//  optimal implementation of anagram
function areAnagrams(str1, str2) {
  var hashMap = {};
  if (str1.length !== str2.length) {
    return false;
  }
  for(var i=0; i<str1.length; i++) {
    if (!hashMap[str1[i]]) {
      hashMap[str1[i]] = 1;
    } else {
      hashMap[str1[i]]++;
    }
  }
  for(var j=0; j<str2.length; j++) {
    if (hashMap[str2[j]]) {
      hashMap[str2[j]]--;
    } else {
      return false;
    }
  }
  return true;
  console.log(hashMap);
}

console.log(areAnagrams("mlllary", "lllarmy"));