[LeetCode / Easy] 1. Two-Sum (Python)

💬 Info

• 난이도 : Easy
• 문제 링크 : https://leetcode.com/problems/two-sum/description/
• 풀이 링크 : LeetCode/Easy/59832-2143-1-two-sum.py

Problem

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.

You can return the answer in any order.

Example

예시 1

• Input: nums = [2,7,11,15], target = 9
• Output: [0,1]
• Explanation: Because nums[0] + nums[1] == 9, we return [0, 1].

예시 2

• Input: nums = [3,2,4], target = 6
• Output: [1,2]

예시 3

• Input: nums = [3,3], target = 6
• Output: [0,1]

Constraints

• $2 <= nums.length <= 10^4$
• $-10^9 <= nums[i] <= 10^9$
• $-10^9 <= target <= 10^9$
• Only one valid answer exists

문제 이해

• 배열로 주어진 두 숫자의 합이 target이 경우의 index들을 반환하는 문제

알고리즘

풀이 시간 : 12분

• brute force 사용: 하나씩 비교하는 방식

class Solution:
    def twoSum(self, nums: List[int], target: int) -> List[int]:
        for i in range(len(nums)):
            for j in range(i+1, len(nums)):
                if nums[i] + nums[j] == target:
                    return [i, j]

결과