function solution(letter) {
  var answer = "";
  const morse = {
    ".-": "a",
    "-...": "b",
    "-.-.": "c",
    "-..": "d",
    ".": "e",
    "..-.": "f",
    "--.": "g",
    "....": "h",
    "..": "i",
    ".---": "j",
    "-.-": "k",
    ".-..": "l",
    "--": "m",
    "-.": "n",
    "---": "o",
    ".--.": "p",
    "--.-": "q",
    ".-.": "r",
    "...": "s",
    "-": "t",
    "..-": "u",
    "...-": "v",
    ".--": "w",
    "-..-": "x",
    "-.--": "y",
    "--..": "z",
  };
  const str = letter.split(" ");

  for (const s of str) {
    answer += morse[s];
  }
  return answer;
}

function solution(before, after) {
  var answer = 0;
  const beforeCount = {};
  const afterCount = {};

  for (const char of before) {
    beforeCount[char] = (beforeCount[char] || 0) + 1;
  }

  for (const char of after) {
    afterCount[char] = (afterCount[char] || 0) + 1;
  }

  for (const key in beforeCount) {
    if (beforeCount[key] !== afterCount[key]) {
      return (answer = 0);
    }
  }

  return (answer = 1);
}

function solution(emergency) {
  const sorted = [...emergency].sort((a, b) => b - a);
  const rankMap = new Map();

  sorted.forEach((value, index) => {
    rankMap.set(value, index + 1);
  });

  return emergency.map((value) => rankMap.get(value));
}

function solution(score) {
  const averages = score.map(([english, math]) => (english + math) / 2);
  const sortedAverages = [...averages].sort((a, b) => b - a);

  return averages.map((avg) => sortedAverages.indexOf(avg) + 1);
}

function solution(participant, completion) {
  const obj = {};

  for (const p of participant) {
    if (obj[p]) {
      obj[p] += 1;
    } else {
      obj[p] = 1;
    }
  }

  for (const c of completion) {
    obj[c] -= 1;
  }

  for (const key in obj) {
    if (obj[key] > 0) {
      return key;
    }
  }
}