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Program: Implement selection sort in java.
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(", ");
}
}
}
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Output: |
2, 7, 10, 34, 42, 56, 67, 88,
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Java Sorting Algorithms Examples
- Implement bubble sort in java.
- Implement selection sort in java.
- Implement insertion sort in java.
- Implement quick sort in java.
- Implement merge sort in java.
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Class, Constructor and Primitive data types
Class is a template for multiple objects with similar features and it is a blue print for objects. It defines a type of object
according to the data the object can hold and the operations the object can perform. Constructor is a special kind of method that
determines how an object is initialized when created. Primitive data types are 8 types and they are: byte, short, int, long, float,
double, boolean, char.
The greatest obstacle to discovery is not ignorance; it is the illusion of knowledge.
-- Daniel J. Boorstin
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