Problem Statement

Given two 2D arrays of item-value pairs, named items1 and items2.

• item[i] = [value_i, weight_i], where each value_i in these arrays is unique within its own array and is paired with a weight_i.

Combine these arrays such that if a value appears in both, its weights are summed up. The final merged array should be sorted based on the value_i.

Examples

1. Example 1:

   • Input: items1 = [[1,2],[4,3]], items2 = [[2,1],[4,3],[3,4]]
   • Expected Output: [[1,2],[2,1],[3,4],[4,6]]
   • Justification: Item 1 has value 2 in items1 and doesn't exist in items2, item 2 has value 1 in items2, item 4 is summed up.

2. Example 2:

   • Input: items1 = [[5,5]], items2 = [[5,10]]
   • Expected Output: [[5,15]]
   • Justification: Item 5 exists in both arrays, so their values are summed.

3. Example 3:

   • Input: items1 = [[1,1],[2,2]], items2 = [[3,3]]
   • Expected Output: [[1,1],[2,2],[3,3]]
   • Justification: All items are unique across items1 and items2, so they remain unchanged.

Constraints:

• 1 <= items1.length, items2.length <= 1000
• items1[i].length == items2[i].length == 2
• 1 <= value_i, weight_i <= 1000
• Each value_i in items1 is unique.
• Each value_i in items2 is unique.

Try it yourself

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