import java.util.Random;
import java.util.Arrays;
public class Select
{
//select sort
public static void selectSort(int arr[])
{
int n = arr.length;
// One by one move boundary of unsorted subarray
for (int i = 0; i < n-1; i++)
{
// Find the minimum element in unsorted array
int min_idx = i;
for (int j = i+1; j < n; j++)
if (arr[j] < arr[min_idx])
min_idx = j;
// Swap the found minimum element with the first
// element
int temp = arr[min_idx];
arr[min_idx] = arr[i];
arr[i] = temp;
}
}
//generate an array with random elements
public static int [] getArray(int size)
{
int [] array = new int[size];
Random r = new Random();
for(int i = 0; i < size; i++)
array[i] = r.nextInt(100);
return array;
}
//display an array
public static void displayArray(int arr[])
{
for(int e : arr)
System.out.printf("%5d", e);
System.out.println();
}
public static void main(String args[])
{
long start, end;
int [] array;
int [] array2;
int size = 100000;
//create two same arrays
array = getArray(size);
array2 = Arrays.copyOf(array, array.length);
//sort a huge array with select sort
start = System.currentTimeMillis();
selectSort(array);
end = System.currentTimeMillis();
System.out.printf("Bubble sort time: %10f%n", (end-start)/1000000.0);
//sort the array with build-in sort function in Arrays class
start = System.currentTimeMillis();
Arrays.sort(array2);
end = System.currentTimeMillis();
System.out.printf("Build-in sort time: %10f%n", (end-start)/1000000.0);
//validate select sort
if(Arrays.equals(array, array2))
System.out.println("Bubble sort is validated ...");
else
System.out.println("Bubble sort does not work correctly ...");
}
}