DSA/SortingAlgo: InsertionSort

前言: 插入排序法是將元素反覆的插至正確的位置，事實上是透過賦值的方式，挪動元素，再將要插入的元素(pivot, key)，放入正確的位置。

def insertionSort(arr):
    n = len(arr)
    for i in range(1, n):
        key = arr[i]
        j = i - 1
        while (j >= 0 and arr[j]>key):
            arr[j + 1] = arr[j]
            j -= 1
        arr[j + 1] = key

arr = [4, 7, 2, 9, 1, 3, 6, 5, 8, 0]
insertionSort(arr)
print(arr)

import java.util.Arrays;

class Main {
    public static void main(String[] args) {
        int arr[] = {4, 7, 2, 9, 1, 3, 6, 5, 8, 0};
        System.out.println("After Sorting: ");
        insertionSort(arr);
        System.out.println(Arrays.toString(arr));
    }

    public static void insertionSort(int[] arr) {
        int n = arr.length;
        for (int i = 1; i < n; i++) {
            int key = arr[i];
            int j = i - 1;
            while (j >= 0 && arr[j] > key) {
                arr[j + 1] = arr[j];
                j--;
            }
            arr[j+1] = key;
        }
    }
}