The selection sort is a combination of searching and sorting. During each pass, the unsorted element with the smallest
(or largest) value is moved to its proper position in the array. The number of times the sort passes through the array is one less
than the number of items in the array. In the selection sort, the inner loop finds the next smallest (or largest) value and the outer
loop places that value into its proper location.
Selection sort is not difficult to analyze compared to other sorting algorithms since none of the loops depend on the data
in the array. Selecting the lowest element requires scanning all n elements (this takesn − 1 comparisons) and then swapping it into the
first position. Finding the next lowest element requires scanning the remaining n − 1 elements and so on,
for (n − 1) + (n − 2) + ... + 2 + 1 = n(n − 1) / 2 ∈ Θ(n2) comparisons. Each of these scans requires one swap for n − 1 elements.
package com.java2novice.algos;
public class MySelectionSort {
public static int[] doSelectionSort(int[] arr){
for (int i = 0; i < arr.length - 1; i++)
{
int index = i;
for (int j = i + 1; j < arr.length; j++)
if (arr[j] < arr[index])
index = j;
int smallerNumber = arr[index];
arr[index] = arr[i];
arr[i] = smallerNumber;
}
return arr;
}
public static void main(String a[]){
int[] arr1 = {10,34,2,56,7,67,88,42};
int[] arr2 = doSelectionSort(arr1);
for(int i:arr2){
System.out.print(i);
System.out.print(", ");
}
}
}
Everything in java is an object, except primitives. Primitives are
int, short, long, boolean, etc. Since they are not objects, they cannot
return as objects, and collection of objects. To support this, java provides
wrapper classes to move primitives to objects. Some of the wrapper classes
are Integer, Long, Boolean, etc.
Famous Quotations
Education is what remains after one has forgotten what one has learned in school.
-- Albert Einstein
About Author
I'm Nataraja Gootooru, programmer by profession and passionate about technologies. All
examples given here are as simple as possible to help beginners. The source code is compiled and tested in my dev environment.
If you come across any
mistakes or bugs, please email me to [email protected] or you can comment on the page.