Package g1501_1600.s1526_minimum_number_of_increments_on_subarrays_to_form_a_target_array

Class Solution

java.lang.Object
g1501_1600.s1526_minimum_number_of_increments_on_subarrays_to_form_a_target_array.Solution
public class Solution extends java.lang.Object
1526 - Minimum Number of Increments on Subarrays to Form a Target Array.

Hard

You are given an integer array target. You have an integer array initial of the same size as target with all elements initially zeros.

In one operation you can choose any subarray from initial and increment each value by one.

Return the minimum number of operations to form a target array from initial.

The test cases are generated so that the answer fits in a 32-bit integer.

Example 1:

Input: target = [1,2,3,2,1]

Output: 3

Explanation: We need at least 3 operations to form the target array from the initial array.

[0,0,0,0,0 ] increment 1 from index 0 to 4 (inclusive).

[1, 1,1,1 ,1] increment 1 from index 1 to 3 (inclusive).

[1,2, 2 ,2,1] increment 1 at index 2.

[1,2,3,2,1] target array is formed.

Example 2:

Input: target = [3,1,1,2]

Output: 4

Explanation: [0,0,0,0 ] -> [1,1,1, 1 ] -> [1 ,1,1,2] -> [2 ,1,1,2] -> [3,1,1,2]

Example 3:

Input: target = [3,1,5,4,2]

Output: 7

Explanation: [0,0,0,0,0 ] -> [1 ,1,1,1,1] -> [2 ,1,1,1,1] -> [3,1, 1,1,1 ] -> [3,1, 2,2 ,2] -> [3,1, 3,3 ,2] -> [3,1, 4 ,4,2] -> [3,1,5,4,2].

Constraints:

  • 1 <= target.length <= 105
  • 1 <= target[i] <= 105

  • Constructor Summary

    Constructors
    Constructor
    Description
    Solution()
     

  • Method Summary

    Modifier and Type
    Method
    Description
    int
    minNumberOperations(int[] target)
     

    Methods inherited from class java.lang.Object

    clone, equals, finalize, getClass, hashCode, notify, notifyAll, toString, wait, wait, wait

  • Constructor Details

    • Solution

      public Solution()

  • Method Details

    • minNumberOperations

      public int minNumberOperations(int[] target)