#3229

Minimum Operations to Make Array Equal to Target

Hard
ArrayDynamic ProgrammingStackGreedyMonotonic StackGreedyArray
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Approaches

Brute ForceOptimal
Complexity Comparison
Brute ForceOptimal Solution
Time
O(n²)
O(n)
Space
O(1)
O(n)
💡

Intuition

Time O(n)Space O(n)

The optimal solution leverages the concept of differences between the two arrays and uses a greedy approach to minimize operations by adjusting contiguous segments of the array.

⚙️

Algorithm

3 steps
  1. 1Step 1: Calculate the difference array, diff[i] = nums[i] - target[i].
  2. 2Step 2: Traverse the difference array and count the number of contiguous segments where the difference is not zero.
  3. 3Step 3: Each contiguous segment represents one operation, so return the count of segments.
solution.py9 lines
1def minOperations(nums, target):
2    diff = [nums[i] - target[i] for i in range(len(nums))]
3    ops = 0
4    for i in range(len(diff)):
5        if diff[i] != 0:
6            ops += 1
7            while i < len(diff) and diff[i] != 0:
8                i += 1
9    return ops

Complexity note: The complexity is linear because we only traverse the array a couple of times, once to compute differences and once to count segments.

  • 1Understanding the difference between the two arrays allows for a more efficient solution.
  • 2Contiguous segments of differences can be adjusted in one operation.

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