array-palindrome

/**
QUESTION
given an array of strings, determine if the strings can be rearranged
to form a palindrome.
**/

function possiblePalidrome(arr) {
  var totalLetters = arr.reduce((total, set) => {
    total += set.length;
    return total;
  }, 0);
  var dictionary = {};
  var dictionaryKeys = [];
  var possible = totalLetters %2 === 0 ? 0 : 1;
  var unmatchedLetters = 0;
  
  for(var i = 0; i < arr.length; i++){
    for(var j = 0; j < arr[i].length; j++){
      if(dictionary[arr[i][j]]) {
        dictionary[arr[i][j]]++;
      } else {
        dictionary[arr[i][j]] = 1;
      }
    }
  }
  
  dictionaryKeys = Object.keys(dictionary);
  for(var k = 0; k < dictionaryKeys.length; k++) {
    if(unmatchedLetters > possible) {
      return false;
    }
    if(dictionary[dictionaryKeys[k]] % 2 !== 0){
      unmatchedLetters++;
    }
  }
  return true;
}

console.log(possiblePalidrome(['aa','abba', 'cc']))
console.log(possiblePalidrome(['aa','abbaw', 'ccc']))
console.log(possiblePalidrome(['a','b','c']))
console.log(possiblePalidrome(['a','abba','cac']))