How to Search an Element in Java Array with Example? ArrayUtils Tutorial

find an index of the object in Array

While programming in Java, many times we need to check if a String array contains a particular String or an integer array contains a number or not. Though array is an object in Java but it does not provide any convenient method to perform searching elements or finding elements. Sometimes you even need an index of an item stored in Array, unfortunately, Java API does not provide any direct method. Thanks to Open Source Apache Commons provides a utility class called ArrayUtils which allows you to check for an Item in Array, find its index in the array, find its lastIndex in Array and perform several other common operations. 

[Solved] How to solve a coin change problem in Java? Example

The coin change problem is one of the popular coding interview question and knowing how to solve this problem can help you during coding interview. It's also useful to learn a couple of tricks and data structure. This problem somewhat has to do with arrays, so we shall be discussing what an array is, But before we dive into this. we need to understand the problem. We are about to solve a coin problem by determining how many possible ways an amount can be paid. Suppose, Mary is a Businesswoman who deals with coin change. 

[Solved] How to find all pairs which add up to a given value in an Integer Array in Java? Example

Hello guys, if you are preparing for programming job interview then you know that the problem of finding all pairs which adds up to a given value in a give array is a popular array based coding question. This question is also known as Two sum problem because you need to find pair of two elements in the array whose sum is equal to given number. For example, you have given an array of integers with values {1, 2, 3, 4, 5, 6} and you need to find all the pairs whose sum is equal to 5. In this case, there are two such pairs (1, 4) and (2, 3) so your program needs to print them into console.