Tip 1: Be clear about the basics of data structures and learn how to build the logic for a problem. Then, try to find a solution, starting from a brute force approach and progressing to an optimized solution.
Tip 2: As a fresher, it's important to have at least two good projects. You should definitely have a clear understanding of what your project is about and be able to answer related questions during the interview.
Tip 3: The number of DSA questions you solve doesn't matter. What matters is having an understanding of how to approach a particular question, knowing which data structures to use, and being able to find a better solution.
Tip 1: Highlight the technical skills in which you excel.
Tip 2: Have at least two good projects on your resume.



We cannot use the element at a given index twice.
Try to do this problem in O(N) time complexity.
Step 1: Initialize an empty hash map (numToIndexMap) to store the numbers seen so far and their corresponding indices.
Step 2: Iterate over the array using a for loop.
For each number nums[i], calculate the difference diff between the target and the current number (diff = target - nums[i]).
Step 3: Check if diff exists in numToIndexMap. If it does, it means the two numbers that add up to the target have been found. Return their indices [i, numToIndexMap.get(diff)].
Step 4: If diff does not exist in the map, store the current number and its index in numToIndexMap.
Step 5: If no such pair is found by the end of the loop, return null. (However, according to the problem constraints, a solution is guaranteed, so this case won't occur.)

Here's your problem of the day
Solving this problem will increase your chance to get selected in this company
What is recursion?