package com.class01;


public class Code03_SelectionSort {
    /***
     * Description: TODO Selection sort
     * @Author: Uriel
     * @param    arr
     * @return: void
     * @date: 2022-06-25 09:52
     */
    public static void selectSort(int[] arr) {
        // Boundary conditions to determine
        if (arr == null || arr.length < 2) {
            return;
        }
        // 0 ~ n-1
        // 1 ~ n-1
        // 2 ~ n-1
        // ....
        // i ~ n-1
        for (int i = 0; i < arr.length; i++) {
            int minValIndex = i; // 假设第一个数是最小的
            for (int j = i + 1; j < arr.length; j++) {
                minValIndex = arr[j] < arr[minValIndex] ? j : minValIndex;
            }
            swap(arr, i, minValIndex);
        }
    }

    /***
     * Description: TODO Exchange of two Numbers
     * @param    arr
     * @param    i
     * @param    j
     * @return: void
     */
    public static void swap(int[] arr, int i, int j) {
        int tmp = arr[i];
        arr[i] = arr[j];
        arr[j] = tmp;
    }

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

    //The entrance of program
    public static void main(String[] args) {
        int[] arr = {7, 1, 3, 5, 1, 6, 8, 1, 3, 5, 7, 5, 6};
        printArray(arr);
        selectSort(arr);
        printArray(arr);
    }
}