Solving Leetcode Interviews in Seconds with AI: Pizza With 3n Slices
Introduction
In this blog post, we will explore how to solve the LeetCode problem "1388" using AI. LeetCode is a popular platform for preparing for coding interviews, and with the help of AI tools like Chatmagic, we can generate solutions quickly and efficiently - helping you pass the interviews and get the job offer without having to study for months.
Problem Statement
There is a pizza with 3n slices of varying size, you and your friends will take slices of pizza as follows: You will pick any pizza slice. Your friend Alice will pick the next slice in the anti-clockwise direction of your pick. Your friend Bob will pick the next slice in the clockwise direction of your pick. Repeat until there are no more slices of pizzas. Given an integer array slices that represent the sizes of the pizza slices in a clockwise direction, return the maximum possible sum of slice sizes that you can pick. Example 1: Input: slices = [1,2,3,4,5,6] Output: 10 Explanation: Pick pizza slice of size 4, Alice and Bob will pick slices with size 3 and 5 respectively. Then Pick slices with size 6, finally Alice and Bob will pick slice of size 2 and 1 respectively. Total = 4 + 6. Example 2: Input: slices = [8,9,8,6,1,1] Output: 16 Explanation: Pick pizza slice of size 8 in each turn. If you pick slice with size 9 your partners will pick slices of size 8. Constraints: 3 * n == slices.length 1 <= slices.length <= 500 1 <= slices[i] <= 1000
Explanation
Here's the solution to the pizza slicing problem, designed for optimal efficiency:
- Dynamic Programming: The problem can be modeled as selecting non-adjacent elements from a circular array. We can transform the circular array into two linear arrays and apply dynamic programming to find the maximum sum of
nnon-adjacent elements. - Overlapping Subproblems: Dynamic programming efficiently addresses the overlapping subproblems inherent in this type of optimization.
Two Linear Cases: Since it is a circular array, we consider two cases. One including the first element of the original array and other excluding the first element of the original array.
Time Complexity: O(n2), Space Complexity: O(n2)
Code
def maxSizeSlices(slices):
"""
Calculates the maximum possible sum of slice sizes that you can pick.
Args:
slices: A list of integers representing the sizes of the pizza slices.
Returns:
The maximum possible sum of slice sizes that you can pick.
"""
def solve(arr, n):
k = len(arr)
dp = [[0] * (n + 1) for _ in range(k + 1)]
for i in range(1, k + 1):
for j in range(1, n + 1):
dp[i][j] = max(dp[i-1][j], (arr[i-1] + dp[i-2][j-1]) if i > 1 else arr[i-1])
return dp[k][n]
m = len(slices) // 3
return max(solve(slices[1:], m), solve(slices[:-1], m))