anagram.ts

function hasLetter(dict: object, letter: char): boolean {
  return dict.hasOwnProperty(letter);
}

function updateLetterStat(dict: object, letter: char): void {
  if (!hasLetter(dict, letter)) {
    dict[letter] = 0;
  }
  
  dict[letter] += 1;
}

function isAnagram(a: string, b: string): void {
  const dictionary = {};
  
  if (a.length !== b.length) {
    console.log(false);
    return;
  }
  
  if (a === b) {
    console.log(true);
    return;
  }
  
  for (let i = 0; i < a.length; i++) {
    const aChar = a[i];
    const bChar = b[i];
    
    updateLetterStat(dictionary, aChar);
    updateLetterStat(dictionary, bChar);
  }
  
  const keys = Object.keys(dictionary);
  
  for (let i = 0; i < keys.length; i++) {
    const char = keys[i];
    const value = dictionary[char];
    
    if (value % 2 !== 0) {
      console.log(false);
      return;
    }
  }
  
  console.log(true);
}

isAnagram('стационар', 'соратница');
isAnagram('покраснение', 'пенсионерка');
isAnagram('покраснение', 'пенсионеркq');