export function compress(chars: string[]) {
  let L = 0;
  let R = 1;
  const N = chars.length;
  let currentCounter = 1;

  while (L <= N && R <= N) {
    const curL = chars[L];
    const curR = chars[R];

    if (curL !== curR || curR === undefined) {
      if (currentCounter > 1) {
        [...("" + currentCounter)].forEach((item, i) => {
          chars[L + 1 + i] = item;
        });
        currentCounter = 1;
      }
      L = R;
    }

    if (curL === curR) {
      currentCounter++;
      chars[R] = " ";
    }

    R++;
  }

  for (let i = chars.length - 1; i >= 0; i--) {
    if (chars[i] === " ") {
      chars.splice(i, 1);
    }
  }

  return chars.length;
}