#3576

Transform Array to All Equal Elements

Medium
ArrayGreedyGreedyArray
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Approaches

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

Intuition

Time O(n)Space O(1)

Use a greedy approach to fix mismatches as we traverse the array. Count the operations needed to make all elements equal.

⚙️

Algorithm

3 steps
  1. 1Step 1: Initialize a counter for operations needed.
  2. 2Step 2: Traverse the array and whenever a mismatch occurs (1 followed by -1), increment the operation counter and flip the next element.
  3. 3Step 3: After traversal, check if the total operations are within k.
solution.py7 lines
1def canTransform(nums, k):
2    ops = 0
3    for i in range(len(nums) - 1):
4        if nums[i] != nums[i + 1]:
5            ops += 1
6            nums[i + 1] *= -1
7    return ops <= k

Complexity note: The linear complexity comes from a single pass through the array to count operations.

  • 1Mismatches can be fixed in pairs.
  • 2The number of operations needed can be counted in a single pass.

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