Problem Statement

Given an array of positive integers nums, return the minimum number of operations required to make all elements of nums 0.

In one operation, you must:

• Select a positive integer n such that n is less than or equal to the smallest positive element in nums.
• Subtract n from every non-zero element in nums.

Examples

• Example 1:

  • Input: nums = [3,3,2]
  • Expected Output: 2
  • Justification: Subtract 2 from all non-zero elements to get [1,1,0]. Then, subtract 1 to get all zeros. 2 steps are required.

• Example 2:

  • Input: [1,2,3,4,5]
  • Expected Output: 5
  • Justification: Since all elements are unique, each step involves subtracting 1 from a unique non-zero element, requiring 5 steps to turn the array into zeros.

• Example 3:

  • Input: [4,4,4,3,3,2,2,1]
  • Expected Output: 4
  • Justification: After removing duplicates, we have [4,3,2,1]. Each number represents a unique subtraction step, hence 4 steps are needed.

Try it yourself

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