#1959

Minimum Total Space Wasted With K Resizing Operations

Medium
ArrayDynamic ProgrammingPrefix SumDynamic ProgrammingPrefix Sum
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Approaches

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

Intuition

Time O(n * k)Space O(n * k)

The optimal approach uses dynamic programming to efficiently calculate the minimum wasted space by storing intermediate results. This avoids redundant calculations and allows us to build solutions incrementally.

⚙️

Algorithm

3 steps
  1. 1Step 1: Create a DP array where dp[i][j] represents the minimum wasted space using the first i elements with j resizes.
  2. 2Step 2: Iterate through each element and each possible number of resizes.
  3. 3Step 3: For each state, calculate the total wasted space based on previous states and update the DP array.
solution.py11 lines
1def minSpaceWasted(nums, k):
2    n = len(nums)
3    dp = [[float('inf')] * (k + 1) for _ in range(n + 1)]
4    dp[0][0] = 0
5    for i in range(1, n + 1):
6        total = 0
7        for j in range(i, 0, -1):
8            total += nums[j - 1]
9            for resizes in range(k + 1):
10                dp[i][resizes] = min(dp[i][resizes], dp[j - 1][resizes - 1] + total - nums[j - 1])
11    return min(dp[n])

Complexity note: This complexity is due to the nested loops iterating over the number of elements and the number of resizing operations, leading to a manageable growth in states compared to the brute force approach.

  • 1Dynamic programming can significantly reduce the number of calculations by storing intermediate results.
  • 2Understanding how to break down the problem into smaller subproblems is crucial for applying DP effectively.

Solutions and explanations are original Tejav content. Problem titles © LeetCode — use the LeetCode button above for the full problem statement.