function diamond (height) {
  let result = ''
  for (let row = 0; row < height; row++) {
    const spaces = Math.abs(row - Math.floor(height / 2))
    const stars = height - spaces * 2
    result += ' '.repeat(spaces) + '*'.repeat(stars) + ' '.repeat(spaces) + '\n'
  }
  return result
}

function getPersonWithMostFriendsByName (people, friendName) {
  let max = 0
  let name

  for (const user of people) {
    let total = 0
    for (const friend of user.friends) {
      if (friend.name === friendName) {
        total++
      }
    }

    if (total > max) {
      name = user.name
      max = total
    }
  }

  return name
}

const getSearchedNameFriendsCount = (friends, name) => friends
  .filter((friend) => friend.name === name)
  .length;

const getPersonWithMostFriendsByName = (people, friendName) => {
  const { name } = people
    .map(({ name, friends }) => ({
      name, count: getSearchedNameFriendsCount(friends, friendName)
    }))
    .reduce((acc, current) => (acc.count >= current.count ? acc : current));
  return name;
};