Selection Sort: Difference between revisions

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Line 13: Line 13:
<syntaxhighlight lang='java'>
<syntaxhighlight lang='java'>
     public void sort(int[] a) {
     public void sort(int[] a) {
        if (a.length == 0 || a.length == 1) {
            return;
        }


         for(int i = 0; i < a.length - 1; i ++) {
         for(int i = 0; i < a.length - 1; i ++) {

Revision as of 23:32, 6 August 2018

Internal

Overview

Selection sort scans the input array from left to right, determining the minimum elements in the subarray spanning from the current position to the end of the input array and then swap the current element with the minimum.

It is an in-place sorting algorithm.

The best case and the worst case running time are both Θ(n2).

    public void sort(int[] a) {

        for(int i = 0; i < a.length - 1; i ++) {

            int minIndex = i;

            for(int j = i + 1; j < a.length; j ++) {

                if (a[j] < a[minIndex]) {

                    minIndex = j;
                }
            }

            if (i != minIndex) {

                //
                // swap
                //
                
                int tmp = a[i];
                a[i] = a[minIndex];
                a[minIndex] = tmp;
            }
        }
    }