Easy•Array · Hash Map

Two Sum

Given an array of numbers and a target, return the indexes of two different numbers whose sum equals the target.

In very simple words

Find two numbers that make the target, but return their positions. You cannot use the same position twice.

[2, 7, 11, 15], target = 9

2 + 7 = 9 → return [0, 1]

[3, 2, 4], target = 6

2 + 4 = 6 → return [1, 2]

Important: return indexes such as [0, 1], not the values [2, 7].

Have you solved it before?

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Read one hint, pause, and try again before opening the next.

Step 1

Find two different positions in the array whose values add up to the target. Return the positions, not the values.

For nums = [2, 7, 11, 15] and target = 9, return [0, 1] because nums[0] + nums[1] = 9.

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