Problem statement: Sort the given array in ascending order such that elements will be arranged from smallest to largest. Consider an illustration below:
Let the original array be as follows:
-5 | -9 | 8 | 12 | 1 | 3 |
Array generated after sorting the above array is as follows:
-9 | -5 | 1 | 3 | 8 | 12 |
- Elements are sorted in such a way that the smallest element will appear on the extreme left which in this case is -9. The largest element will appear on the extreme right which in this case is 12.
Approaches:
- Using bubble sort(naive)
- Using sort() method of arrays class(optimal)
Approach 1: Using Bubble sort
Algorithm:
- Compare adjacent elements with each other.
- Use nested for loop to keep track.
- Swap the elements if the first element is greater than the second element.
Example
// Java Program to Sort Elements of an Array // in Ascending Order // Main class class GFG {
// Declaration global variable length
static int length;
// Method 1
// To print the array
public static void printArray( int [] array)
{
// Iterating using for loops
for ( int i = 0 ; i < length; i++) {
System.out.print(array[i] + " " );
}
System.out.println();
}
// Method 2
// To sort an array
public static void sortArray( int [] array)
{
int temporary = 0 ;
// Sort the array 'arr' elements in ascending order
// using nested for loops
for ( int i = 0 ; i < length; i++) {
for ( int j = i + 1 ; j < length; j++) {
if (array[i] > array[j]) {
temporary = array[i];
array[i] = array[j];
array[j] = temporary;
}
}
}
// Displaying elements of array after sorting
System.out.println(
"Elements of array sorted in ascending order: " );
printArray(array);
}
// Method 3
// Main driver method
public static void main(String[] args)
{
// Initializing custom array elements
// The array contains 6 elements.
int [] array = new int [] { - 5 , - 9 , 8 , 12 , 1 , 3 };
// Initialize length
length = array.length;
// Displaying elements of original array
System.out.print( "Elements of original array: " );
// Call printArray method
printArray(array);
// Call sortArray method
sortArray(array);
}
} |
Elements of original array: -5 -9 8 12 1 3 Elements of array sorted in ascending order: -9 -5 1 3 8 12
Time Complexity: O(n^2), where n is the length of an array.
Approach 2: Using sort() method of Arrays class
The sort() method is a java.util.Arrays class method used to sort array elements. It by default sorts of array elements in ascending order.
Syntax:
Arrays.sort(arrayName);
Parameters: Array to be sorted
Return Type: NA
Example
// Java Program to sort the elements of an array // in Ascending Order by Inbuilt Methods // Importing Arrays class from java.util package import java.util.Arrays;
// Main class public class GFG {
// Main driver method
public static void main(String[] args)
{
// Initialize array
// The array contains 6 elements.
int [] array = new int [] { - 5 , - 9 , 8 , 12 , 1 , 3 };
// Displaying elements of original array
System.out.print( "Elements of original array: " );
for ( int i = 0 ; i < array.length; i++) {
System.out.print(array[i] + " " );
}
// Using Arrays.sort() method to sort array
// elements in ascending order.
Arrays.sort(array);
System.out.println();
// Displaying elements of array after sorting
System.out.println(
"Elements of array sorted in ascending order : "
+ Arrays.toString(array));
}
} |
Elements of original array: -5 -9 8 12 1 3 Elements of array sorted in ascending order : [-9, -5, 1, 3, 8, 12]
Time Complexity: O(n log(n)), where n is the size of an array.