rust、go、java、python、nodejs各语言内存对比详解

// rust/src/main.rs
#[derive(Debug)]
struct Node {
    left: Option<Box<Node>>,
    right: Option<Box<Node>>,
}

impl Node {
    // 创建新节点
    fn new() -> Self {
        Node { left: None, right: None }
    }

    // 构建满二叉树
    fn build(depth: usize) -> Option<Box<Node>> {
        if depth == 0 {
            return None;
        }
        Some(Box::new(Node {
            left: Self::build(depth - 1),
            right: Self::build(depth - 1),
        }))
    }

    // 遍历树并计算校验值（确保逻辑正确）
    fn check(&self) -> i32 {
        let mut res = 1;
        if let Some(left) = &self.left {
            res += left.check();
        }
        if let Some(right) = &self.right {
            res += right.check();
        }
        res
    }
}

fn main() {
    let max_depth = std::env::args().nth(1).unwrap().parse::<usize>().unwrap_or(5);
    let min_depth = 4;

    // 1. 构建并销毁短命树
    if max_depth >= min_depth + 2 {
        let stretch_tree = Node::build(max_depth + 1);
        println!("Stretch tree check: {}", stretch_tree.as_ref().unwrap().check());
    }

    // 2. 保留长命树
    let long_lived_tree = Node::build(max_depth);

    // 3. 批量构建并遍历不同深度的树
    for depth in (min_depth..=max_depth).step_by(2) {
        let iterations = 1 << (max_depth - depth + min_depth);
        let mut check = 0;

        for _ in 0..iterations {
            let a = Node::build(depth);
            check += a.as_ref().unwrap().check();
        }

        println!("{:>4} trees of depth {:>2} check: {:>4}", iterations, depth, check);
    }

    // 验证长命树未被销毁
    println!("Long lived tree check: {}", long_lived_tree.as_ref().unwrap().check());
}

// go/main.go
package main

import (
	"fmt"
	"os"
	"strconv"
)

type Node struct {
	left  *Node
	right *Node
}

// 构建满二叉树
func NewNode(depth int) *Node {
	if depth == 0 {
		return nil
	}
	return &Node{
		left:  NewNode(depth - 1),
		right: NewNode(depth - 1),
	}
}

// 遍历校验
func (n *Node) Check() int {
	if n == nil {
		return 0
	}
	return 1 + n.left.Check() + n.right.Check()
}

func main() {
	maxDepth := 5
	if len(os.Args) > 1 {
		if d, err := strconv.Atoi(os.Args[1]); err == nil {
			maxDepth = d
		}
	}
	minDepth := 4

	// 1. 短命树
	if maxDepth >= minDepth+2 {
		stretchTree := NewNode(maxDepth + 1)
		fmt.Printf("Stretch tree check: %d\n", stretchTree.Check())
	}

	// 2. 长命树
	longLivedTree := NewNode(maxDepth)

	// 3. 批量构建遍历
	for depth := minDepth; depth <= maxDepth; depth += 2 {
		iterations := 1 << (maxDepth - depth + minDepth)
		check := 0

		for i := 0; i < iterations; i++ {
			a := NewNode(depth)
			check += a.Check()
		}

		fmt.Printf("%4d trees of depth %2d check: %4d\n", iterations, depth, check)
	}

	// 验证长命树
	fmt.Printf("Long lived tree check: %d\n", longLivedTree.Check())
}

# python/main.py
import sys

class Node:
    __slots__ = ('left', 'right')  # 优化：减少对象元数据开销
    def __init__(self):
        self.left = None
        self.right = None

def build_tree(depth):
    if depth == 0:
        return None
    node = Node()
    node.left = build_tree(depth - 1)
    node.right = build_tree(depth - 1)
    return node

def check_tree(node):
    if node is None:
        return 0
    return 1 + check_tree(node.left) + check_tree(node.right)

def main():
    max_depth = 5
    if len(sys.argv) > 1:
        max_depth = int(sys.argv[1])
    min_depth = 4

    # 1. 短命树
    if max_depth >= min_depth + 2:
        stretch_tree = build_tree(max_depth + 1)
        print(f"Stretch tree check: {check_tree(stretch_tree)}")

    # 2. 长命树
    long_lived_tree = build_tree(max_depth)

    # 3. 批量构建遍历
    for depth in range(min_depth, max_depth + 1, 2):
        iterations = 1 << (max_depth - depth + min_depth)
        check = 0

        for _ in range(iterations):
            a = build_tree(depth)
            check += check_tree(a)

        print(f"{iterations:4d} trees of depth {depth:2d} check: {check:4d}")

    # 验证长命树
    print(f"Long lived tree check: {check_tree(long_lived_tree)}")

if __name__ == "__main__":
    main()

// nodejs/main.js
class Node {
  constructor() {
    this.left = null;
    this.right = null;
  }
}

function buildTree(depth) {
  if (depth === 0) {
    return null;
  }
  const node = new Node();
  node.left = buildTree(depth - 1);
  node.right = buildTree(depth - 1);
  return node;
}

function checkTree(node) {
  if (node === null) {
    return 0;
  }
  return 1 + checkTree(node.left) + checkTree(node.right);
}

function main() {
  let maxDepth = 5;
  if (process.argv.length > 2) {
    maxDepth = parseInt(process.argv[2], 10);
  }
  const minDepth = 4;

  // 1. 短命树
  if (maxDepth >= minDepth + 2) {
    const stretchTree = buildTree(maxDepth + 1);
    console.log(`Stretch tree check: ${checkTree(stretchTree)}`);
  }

  // 2. 长命树
  const longLivedTree = buildTree(maxDepth);

  // 3. 批量构建遍历
  for (let depth = minDepth; depth <= maxDepth; depth += 2) {
    const iterations = 1 << (maxDepth - depth + minDepth);
    let check = 0;

    for (let i = 0; i < iterations; i++) {
      const a = buildTree(depth);
      check += checkTree(a);
    }

    console.log(`${iterations.toString().padStart(4)} trees of depth ${depth.toString().padStart(2)} check: ${check.toString().padStart(4)}`);
  }

  // 验证长命树
  console.log(`Long lived tree check: ${checkTree(longLivedTree)}`);
}

main();

// java/BinaryTrees.java
public class BinaryTrees {
    static class Node {
        Node left;
        Node right;
    }

    // 构建满二叉树
    static Node buildTree(int depth) {
        if (depth == 0) {
            return null;
        }
        Node node = new Node();
        node.left = buildTree(depth - 1);
        node.right = buildTree(depth - 1);
        return node;
    }

    // 遍历校验
    static int checkTree(Node node) {
        if (node == null) {
            return 0;
        }
        return 1 + checkTree(node.left) + checkTree(node.right);
    }

    public static void main(String[] args) {
        int maxDepth = 5;
        if (args.length > 0) {
            maxDepth = Integer.parseInt(args[0]);
        }
        int minDepth = 4;

        // 1. 短命树
        if (maxDepth >= minDepth + 2) {
            Node stretchTree = buildTree(maxDepth + 1);
            System.out.printf("Stretch tree check: %d%n", checkTree(stretchTree));
        }

        // 2. 长命树
        Node longLivedTree = buildTree(maxDepth);

        // 3. 批量构建遍历
        for (int depth = minDepth; depth <= maxDepth; depth += 2) {
            int iterations = 1 << (maxDepth - depth + minDepth);
            int check = 0;

            for (int i = 0; i < iterations; i++) {
                Node a = buildTree(depth);
                check += checkTree(a);
            }

            System.out.printf("%4d trees of depth %2d check: %4d%n", iterations, depth, check);
        }

        // 验证长命树
        System.out.printf("Long lived tree check: %d%n", checkTree(longLivedTree));
    }
}