BasicSorting.java

import java.util.*;

public class BasicSorting {

    // Bubble Sort
    public static void bubbleSort(int arr[]){
        for(int turn=0; turn<arr.length-1; turn++){
            for(int j=0; j<arr.length-1-turn; j++){
                if(arr[j] > arr[j+1]){
                    int temp = arr[j];
                    arr[j] = arr[j+1];
                    arr[j+1] = temp;
                }
            }
        }
    }

    public static void printArr(int arr[]){
        for(int i=0; i<arr.length; i++){
            System.out.print(arr[i]+" ");
        }
        System.out.println();
    }

// -----------------------------------------------------------------------------------------

    // Selection Sort
    public static void selectionSort(int arr[]){
        for(int i=0; i<arr.length-1; i++){
            int minPos = i;
            for(int j=i+1; j<arr.length; j++){
                if(arr[minPos] > arr[j]){
                    minPos = j;
                }
            }
            int temp = arr[minPos];
            arr[minPos] = arr[i];
            arr[i] = temp;
        }
    }

    //Insertion Sort
    public static void insertionSort(int arr[]){
        for(int i=1; i<arr.length; i++){
            int curr = arr[i]; 
            int prev = i-1; 
            while(prev >= 0 && arr[prev] > curr){
                arr[prev+1] = arr[prev];
                prev--;
            }
            arr[prev+1] = curr;
        }
    }

    public static void countingSort(int arr[]){
        int largest = Integer.MIN_VALUE;
        for(int i=0; i<arr.length; i++){
            largest = Math.max(largest, arr[i]);
        }

        int count[] = new int[largest+1];
        for(int i=0; i<arr.length; i++){
            count[arr[i]]++;
        }

        int j=0; 
        for(int i=0; i<count.length; i++){
            while(count[i] > 0){
                arr[j] = i; 
                j++;
                count[i]--;
            }
        }
    }

public static void main(String args[]){
    // int arr[] = {5,4,1,3,2};
    int arr[] = {1,4,1,3,2,4,3,7};
    // insertionSort(arr);
    // selectionSort(arr);
    // Arrays.sort(arr,0,3);
    // Arrays.sort(arr,0,3, Collections.reverseOrder());
    // countingSort(arr);
    printArr(arr);
// -----------------------------------------------------------------------------------------

        // int arr[] = {5,4,1,3,2};
        // bubbleSort(arr);
        // printArr(arr);
    }
}