How to Compare Two Arrays in Java without built-in functions
In this blog, we will see how to compare two arrays in java without in-built functions. This will be asked in the most of the interview questions.
In the below snippet, we have done the following:
- Created two arrays of same datatype and assigned those with some elements
- Created a helper class with parameters of these two arrays
- Inside the helper class, to compare the arrays we have done the following
- Firstly, we compared both the declared arrays length are equal or not using arrayname.length() and returned the value
- Then, we have iterated a for loop based on array.length() and then compared the arrays index is equal or not and returned the value.
- In the main method, we mentioned an If condition which will validate the result based on the returned value.
package Javaprograms;
public class CompareArraysWithoutInBuiltFunctions {
public static void main(String[] args) {
String a[] = {"apple","bat","cat"};
String b[] = {"apple","bat","catt"};
if(arraysCompareCheck(a, b)){
System.out.println("Both arrays are equal");
}
else
{
System.out.println("Both arrays are not equal");
}
}
public static boolean arraysCompareCheck(String a[], String b[]){
if(a.length!=b.length){
return false;
}
else
{
for(int i=0;i<a.length;i++)
{
if(a[i]!=b[i])
{
return false;
}
}
}
return true;
}
}
Output: -------- Both arrays are not equal
Here, It’s better to use the Object class as a parameter as it is the super class which can inherit all the datatypes and supports whatever the array’s datatype is.
Below is the snippet which uses the Object class as a parameter:
If you’re using an integer array with an object class parameter, Make sure to use the derived datatype Integer instead of Int
package Javaprograms;
public class CompareArraysWithoutInBuiltFunctions {
public static void main(String[] args) {
//String a[] = {"apple","bat","cat"};
//String b[] = {"apple","bat","catt"};
Integer a[] = {1,2,19};
Integer b[] = {1,2,19};
if(arraysCompareCheck(a, b)){
System.out.println("Both arrays are equal");
}
else
{
System.out.println("Both arrays are not equal");
}
}
public static boolean arraysCompareCheck(Object a[], Object b[]){
if(a.length!=b.length){
return false;
}
else
{
for(int i=0;i<a.length;i++)
{
if(a[i]!=b[i])
{
return false;
}
}
}
return true;
}
}
Output: ------- Both Arrays are equal
Please watch the Youtube video for better understanding.
