### System Design Interview Vocabulary Notes

In this post, we will see some of the frequently used concepts/vocabulary in…

September 13, 2019

Given an array nums of n integers and an integer target, find three integers in nums such that the sum is closest to target. Return the sum of the three integers. You may assume that each input would have exactly one solution.

```
Example:
Given array nums = [-1, 2, 1, -4], and target = 1.
The sum that is closest to the target is 2. (-1 + 2 + 1 = 2).
```

The obvious brute force algorithm. The key is to get the closest. You need to compare

`Math.abs(target - calculated_sum)`

Lets look at the optimized solution.

- Sort the array
- Have left and right pointers.
- Keep calculating sum of three values.
- Compare absolute value of difference between targetSum and calculated sum.
- If sum is lesser, need to move left pointer
- else move right pointer.

```
public int threeSumClosest(int[] nums, int target) {
Arrays.sort(nums);
int l = nums.length;
int minDiff = Integer.MAX_VALUE;
int result = 0;
for (int i=0; i<l; i++) {
int j=i+1;
int k=l-1;
while (j < k) {
int sum = nums[i] + nums[j] + nums[k];
if (sum == target) return sum;
else if (sum < target) j++;
else k--;
if (Math.abs(target - sum) < minDiff) {
minDiff = Math.abs(target - sum);
result = sum;
}
}
}
return result;
}
```

In this post, we will see some of the frequently used concepts/vocabulary in…

Problem Statement Given an array of integers, return indices of the two numbers…

Problem Statement Implement atoi which converts a string to an integer…

Problem Statement You are given two non-empty linked lists representing two non…

This is another very useful sorting algorithm based on Heap data structure. Read…

Here are some tips while giving your coding interviews. 1. Never try to jump to…

Introduction In this post we will see following: How to schedule a job on cron…

Introduction There are some cases, where I need another git repository while…

Introduction In this post, we will see how to fetch multiple credentials and…

Introduction I have an automation script, that I want to run on different…

Introduction I had to write a CICD system for one of our project. I had to…

Introduction Java log4j has many ways to initialize and append the desired…