I tried LeetCode every day 167. Two Sum II --Input array is sorted (Python, Go)

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leetcode.com This is the practice of coding interviews for software developers. A total of more than 1,500 coding questions have been posted, and it seems that the same questions are often asked in actual interviews.

Introduction to golang + algorithm I will solve it with go and Python to strengthen the brain.

37th question (problem 167)

Two Sum II - Input array is sorted

the issue's details

Given an array of integers that is already *sorted in ascending order*, find two numbers such that they add up to a specific target number.

The function twoSum should return indices of the two numbers such that they add up to the target, where index1 must be less than index2.

Note:

Your returned answers (both index1 and index2) are not zero-based.

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

Example 1:
Input: numbers = [2,7,11,15], target = 9
Output: [1,2]
Explanation: The sum of 2 and 7 is 9. Therefore index1 = 1, index2 = 2.
Example 2:
Input: numbers = [2,3,4], target = 6
Output: [1,3]
Example 3:
Input: numbers = [-1,0], target = -1
Output: [1,2]

Way of thinking

Loop as many times as there are numbers
Store the value in dic and exit if target-num exists

Answer code

def twoSum(self, numbers, target):
    dic = {}
    for i, num in enumerate(numbers):
        if target-num in dic:
            return [dic[target-num]+1, i+1]
        dic[num] = i

--I'll write it in Go too!

func twoSum(numbers []int, target int) []int {
	m := make(map[int]int)
	for i := 0; i < len(numbers); i++ {
		idx, ok := m[target-numbers[i]]
		if ok {
			return []int{idx + 1, i + 1}
		}
		m[numbers[i]] = i
	}
	return nil
}