3356. Zero Array Transformation II
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You are given an integer array nums of length n and a 2D array queries where queries[i] = [li, ri, vali].
Each queries[i] represents the following action on nums:
- Decrement the value at each index in the range
[li, ri]innumsby at mostvali. - The amount by which each value is decremented can be chosen independently for each index.
A Zero Array is an array with all its elements equal to 0.
Return the minimum possible non-negative value of k, such that after processing the first k queries in sequence, nums becomes a Zero Array. If no such k exists, return -1.
Example 1:
Input: nums = [2,0,2], queries = [[0,2,1],[0,2,1],[1,1,3]]
Output: 2
Explanation:
- For i = 0 (l = 0, r = 2, val = 1):
- Decrement values at indices
[0, 1, 2]by[1, 0, 1]respectively. - The array will become
[1, 0, 1].
- Decrement values at indices
- For i = 1 (l = 0, r = 2, val = 1):
- Decrement values at indices
[0, 1, 2]by[1, 0, 1]respectively. - The array will become
[0, 0, 0], which is a Zero Array. Therefore, the minimum value ofkis 2.
- Decrement values at indices
Example 2:
Input: nums = [4,3,2,1], queries = [[1,3,2],[0,2,1]]
Output: -1
Explanation:
- For i = 0 (l = 1, r = 3, val = 2):
- Decrement values at indices
[1, 2, 3]by[2, 2, 1]respectively. - The array will become
[4, 1, 0, 0].
- Decrement values at indices
- For i = 1 (l = 0, r = 2, val = 1):
- Decrement values at indices
[0, 1, 2]by[1, 1, 0]respectively. - The array will become
[3, 0, 0, 0], which is not a Zero Array.
- Decrement values at indices
Constraints:
1 <= nums.length <= 1050 <= nums[i] <= 5 * 1051 <= queries.length <= 105queries[i].length == 30 <= li <= ri < nums.length1 <= vali <= 5
Hints
Hint 1
Can we apply binary search here?
Hint 2
Utilize a difference array to optimize the processing of queries.