As per the problem statement, we were given some weights and we were told how many days we can utilize to ship those weights. We have to find least capacity required inorder to deliver those weights.

In this approach, we will apply Binary Search algorithm, since the input array is sorted in ascending order, we will use two pointers left and right to point to left and right end of array, and then using a while loop, compute the middle index mid = $\left[\begin{array}{c}\mathrm{left\; +\; right}\\ \mathrm{\_\_\_\_\_\_\_\_\_\_\_\_\_}\\ 2\end{array}\right]$ , then check if the element at mid index, based on the element found at mid index, we can draw three conclusions.

• If the element at mid index is the target, then return the mid index, since the element is same, it can be inserted at this position.
• If the element at mid index is greater than target, since the array is sorted in ascending order, this means that the target lies on left half of the array, so we will update right index to mid-1.
• If the element at mid index is less than target, since the array is sorted in ascending order, this means that the target lies on right half of the array, so we will update left index to mid+1.

If that target is not found, we will return left index as answer, this is where the target element can be inserted.

Complexity Analysis:

Time complexity: Above code runs in O(log n) time where n is the length of input array nums.
Space complexity: O(1).