madein_problem2.js

// problem 2

function lookAndSay(seq) {
  let ans = [];
  let start = 0;

  while (start < seq.length) {
    curr = seq[start];

    step = start;
    while (step < seq.length) {
      if (curr != seq[step]) {
        break;
      }

      step += 1;
    }

    let count = step - start;
    ans.push([count, curr]);
    
    start = step;
  }

  return ans;
}

const sequences = [[1], [1, 1], [2, 1], [1, 2, 1, 1]];
for(let i=0; i<sequences.length; i++){
  console.log(lookAndSay(sequences[i]));
}