Discussion on: Fun With Linear Time: My Favorite Algorithm

function findLeader(votes) {
  // after one vote, we have a leader
  let leader = votes[0];
  let count = 1;

  for (i = 1; i < votes.length; i++) {
    let vote = votes[i]
    if (vote === leader) // the lead may grow
      count++;
    else // or shrink
      count--; 

    // and they may be replaced
    if (count == 0) {
      leader = vote;
      count = 1;
    }
  }
  return leader;
}

console.log(findLeader(['a', 'b', 'a', 'c', 'b', 'c', 'a', 'a'])); // "a"
console.log(findLeader([0, 1, 1, 0, 1, 0, 1, 1])); // "1"