Python实现的快速排序算法

def quick_sort(arr):
    if len(arr)<= 1:
        return arr
    pivot = arr[len(arr)//2]
    left = [x for x in arr if x< pivot]
    middle = [x for x in arr if x == pivot]
    right = [x for x in arr if x > pivot]
    return quick_sort(left) + middle + quick_sort(right)

if __name__ == "__main__":
    arr = [5, 9, 3, 1, 2, 8, 4, 7, 6]
    print("原数组:", arr)
    sorted_arr = quick_sort(arr)
    print("排序后的数组:", sorted_arr)

Java实现的链表数据结构

public class LinkedList {
    Node head; // 头结点

    static class Node {
        int data;
        Node next;

        Node(int data) {
            this.data = data;
            next = null;
        }
    }

    public void append(int data) {
        Node newNode = new Node(data);

        if (head == null) {
            head = newNode;
        } else {
            Node last = head;
            while (last.next != null) {
                last = last.next;
            }
            last.next = newNode;
        }
    }

    public void display() {
        Node currentNode = head;

        while (currentNode != null) {
            System.out.print(currentNode.data + " ");
            currentNode = currentNode.next;
        }
    }

    public static void main(String[] args) {
        LinkedList linkedList = new LinkedList();
        linkedList.append(2);
        linkedList.append(4);
        linkedList.append(6);
        linkedList.append(8);
        
        System.out.println("链表元素：");
        linkedList.display();
    }
}

PHP实现的二分查找算法

function binary_search($arr, $target) {
    $left = 0;
    $right = count($arr) - 1;

    while ($left<= $right) {
        $mid = floor(($left + $right) / 2);

        if ($arr[$mid] == $target) {
            return $mid;
        }

        if ($arr[$mid] > $target) {
            $right = $mid - 1;
        } else {
            $left = $mid + 1;
        }
    }

    return -1; // 未找到目标元素
}

$arr = [1, 3, 5, 7, 9];
$target = 5;
$index = binary_search($arr, $target);

if ($index != -1) {
    echo "目标元素 $target 的索引为 $index";
} else {
    echo "未找到目标元素 $target";
}