minimum-operations-to-convert-all-elements-to-zero
You are given an array nums of size n, consisting of non-negative integers. Your task is to apply some (possibly zero) operations on the array so that all elements become 0.
In one operation, you can select a subarray [i, j] (where 0 <= i <= j < n) and set all occurrences of the minimum non-negative integer in that subarray to 0.
Return the minimum number of operations required to make all elements in the array 0.
Example 1:
Input: nums = [0,2]
Output: 1
Explanation:
- Select the subarray
[1,1](which is[2]), where the minimum non-negative integer is 2. Setting all occurrences of 2 to 0 results in[0,0]. - Thus, the minimum number of operations required is 1.
Example 2:
Input: nums = [3,1,2,1]
Output: 3
Explanation:
- Select subarray
[1,3](which is[1,2,1]), where the minimum non-negative integer is 1. Setting all occurrences of 1 to 0 results in[3,0,2,0]. - Select subarray
[2,2](which is[2]), where the minimum non-negative integer is 2. Setting all occurrences of 2 to 0 results in[3,0,0,0]. - Select subarray
[0,0](which is[3]), where the minimum non-negative integer is 3. Setting all occurrences of 3 to 0 results in[0,0,0,0]. - Thus, the minimum number of operations required is 3.
Example 3:
Input: nums = [1,2,1,2,1,2]
Output: 4
Explanation:
- Select subarray
[0,5](which is[1,2,1,2,1,2]), where the minimum non-negative integer is 1. Setting all occurrences of 1 to 0 results in[0,2,0,2,0,2]. - Select subarray
[1,1](which is[2]), where the minimum non-negative integer is 2. Setting all occurrences of 2 to 0 results in[0,0,0,2,0,2]. - Select subarray
[3,3](which is[2]), where the minimum non-negative integer is 2. Setting all occurrences of 2 to 0 results in[0,0,0,0,0,2]. - Select subarray
[5,5](which is[2]), where the minimum non-negative integer is 2. Setting all occurrences of 2 to 0 results in[0,0,0,0,0,0]. - Thus, the minimum number of operations required is 4.
Constraints:
1 <= n == nums.length <= 1050 <= nums[i] <= 105