Given an array of integers nums and an integer target, return indices of the two numbers such that they add up to target.
Question
Given an array of integers nums and an integer target, return indices of the two numbers such that they add up to target.
Solution
Sure, here is a Python solution for your problem using a dictionary (hashmap) to store the numbers and their indices.
def twoSum(nums, target):
if len(nums) <= 1:
return False
buff_dict = {}
for i in range(len(nums)):
if nums[i] in buff_dict:
return [buff_dict[nums[i]], i]
else:
buff_dict[target - nums[i]] = i
Here is a step by step explanation:
-
Check if the length of the input list is less than or equal to 1. If it is, return False because there are not enough numbers to add up to the target.
-
Create an empty dictionary
buff_dict. -
Loop through the list
numswith the indexi. -
Check if
nums[i]is inbuff_dict. If it is, return a list withbuff_dict[nums[i]]andi. These are the indices of the two numbers that add up to the target. -
If
nums[i]is not inbuff_dict, add a new entry to the dictionary with the key astarget - nums[i]and the value asi. This is because if we subtractnums[i]from the target, we get the other number that we need to find in the list. -
Continue this process until we find a pair of numbers that add up to the target or we have checked all the numbers in the list.
This solution has a time complexity of O(n) because we are making a single pass through the list, and a space complexity of O(n) because in the worst case, we will insert every element of the list into the dictionary.
Similar Questions
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.
1. Two SumEasy53.1K1.8KCompaniesGiven 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 1:Input: nums = [2,7,11,15], target = 9Output: [0,1]Explanation: Because nums[0] + nums[1] == 9, we return [0, 1].Example 2:Input: nums = [3,2,4], target = 6Output: [1,2]Example 3:Input: nums = [3,3], target = 6Output: [0,1] Constraints:2 <= nums.length <= 104
You are given a 0-indexed array nums and an integer target.A 0-indexed array infinite_nums is generated by infinitely appending the elements of nums to itself.Return the length of the shortest subarray of the array infinite_nums with a sum equal to target. If there is no such subarray return -1
Given a sorted array of distinct integers and a target value, return the index if the target is found. If not, return the index where it would be if it were inserted in order.You must write an algorithm with O(log n) runtime complexity. Example 1:Input: nums = [1,3,5,6], target = 5Output: 2Example 2:Input: nums = [1,3,5,6], target = 2Output: 1Example 3:Input: nums = [1,3,5,6], target = 7Output: 4 Constraints:1 <= nums.length <= 104-104 <= nums[i] <= 104nums contains distinct values sorted in ascending order.-104 <= target <= 104
Stefan is working on a coding project that involves finding all pairs in an integer array that sum up to a specific target value.He needs to create a program to automate this task. The program should take an array of integers and a target value as input and then find and display all pairs of integers in the array that add up to the given target.Help Stefan to complete the project.Input format :The first line of input consists of an integer N, representing the number of elements in the array.The second line consists of N space-separated integers, representing the elements of the array.The third line consists of an integer T, which is the sum Stefan wants to find pairs for.Output format :The first line of output prints "Pairs that sum up to [T]:".The following lines print all pairs of integers that sum up to the given target in the format: "X + Y", where X and Y are the integers that sum up to T.Refer to the sample output for formatting specifications.Code constraints :1 ≤ N ≤ 201 ≤ array elements, T ≤ 100Sample test cases :Input 1 :52 3 5 7 810Output 1 :Pairs that sum up to 10:2 + 83 + 7Input 2 :83 8 15 6 12 7 9 217Output 2 :Pairs that sum up to 17:8 + 915 + 2Input 3 :126 10 14 25 3 11 18 1 7 40 15 934Output 3 :Pairs that sum up to 34:25 + 9
Upgrade your grade with Knowee
Get personalized homework help. Review tough concepts in more detail, or go deeper into your topic by exploring other relevant questions.