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exercise.py

def two_sum(nums, target):

# Find two numbers that add up to target

seen = {}

for i, num in enumerate(nums):

diff = target - num

if diff in seen:

return [seen[diff], i]

seen[num] = i

> All tests passed (4/4)

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Two SumMedium

Run Tests

Given an array of integers nums and an integer target, return indices of the two numbers such that they add up to target.

You may assume that each input would have exactly one solution, and you may not use the same element twice.

Example

Input: nums = [2,7,11,15], target = 9

Output: [0, 1]

arrayshash-tabletwo-pointer

solution.py

test_solution.py(read-only)

1def two_sum(nums, target):

2 # Hash map for O(n) lookup

3 seen = {}

4 for i, num in enumerate(nums):

5 diff = target - num

6 if diff in seen:

7 return [seen[diff], i]

8 seen[num] = i

All tests passed4/4

42ms

test_basic_case

test_negative_numbers

test_large_array

test_first_last_elements

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