Amazon | FAANG | OA Coding Questions and Solutions | Set - 25 | 2022

Question

All past online assesments of Amazon can be found using the tag "amazon_oa" in the search bar.

Here is the link : https://www.desiqna.in/tag/amazon_oa

Answer 1

Write a function that takes a list of numbers and a target number, and then returns the number of unique pairs that add up to the target number.

[X, Y] and [Y, X] are considered the same pair, and not unique.

Examples

Example 1:

Input: [1, 1, 2, 45, 46, 46], target = 47

Output: 2

Explanation:

1 + 46 = 47

2 + 45 = 47

Example 2:

Input: [1, 1], target = 2

Output: 1

Explanation:

1 + 1 = 2

Example 3:

Input: [1, 5, 1, 5], target = 6

Output: 1

Explanation:

[1, 5] and [5, 1] are considered the same, therefore there is only one unique pair that adds up to 6.