LeetCode-in-Java
1388. Pizza With 3n Slices
Hard
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.length1 <= slices.length <= 5001 <= slices[i] <= 1000
Solution
public class Solution {
public int maxSizeSlices(int[] slices) {
int n = slices.length;
int third = n / 3;
return Math.max(
maxSizeSlices(slices, 0, n - 2, third), maxSizeSlices(slices, 1, n - 1, third));
}
private int maxSizeSlices(int[] slices, int start, int end, int parts) {
int[] dp = new int[slices.length];
int res = 0;
for (int i = 0; i < parts; i++) {
int prev = 0;
int prevPrev = 0;
for (int j = end; j >= start; j--) {
int curr = dp[j];
dp[j] = slices[j] + prevPrev;
prevPrev = prev;
prev = Math.max(curr, prev);
res = Math.max(res, dp[j]);
}
}
return res;
}
}