1014-capacity-to-ship-packages-within-d-days.js

/**
 * @param {number[]} weights
 * @param {number} D
 * @return {number}
 */
const shipWithinDays = function(weights, D) {
  let left = 0, right = 0;
  for (let w of weights) {
    left = Math.max(left, w);
    right += w;
  }
  while (left < right) {
    let mid = Math.floor((left + right) / 2), need = 1, cur = 0;
    for (let w of weights) {
      if (cur + w > mid) {
        need += 1;
        cur = 0;
      }
      cur += w;
    }
    if (need > D) left = mid + 1;
    else right = mid;
  }
  return left;
}