You can not select more than 25 topics
Topics must start with a letter or number, can include dashes ('-') and can be up to 35 characters long.
70 lines
2.2 KiB
70 lines
2.2 KiB
8 months ago
|
// File: binary_tree_dfs.zig
|
||
|
|
// Created Time: 2023-01-15
|
||
|
|
// Author: codingonion (coderonion@gmail.com)
|
||
|
|
|
||
|
|
const std = @import("std");
|
||
|
|
const inc = @import("include");
|
||
|
|
|
||
|
|
var list = std.ArrayList(i32).init(std.heap.page_allocator);
|
||
|
|
|
||
|
|
// 前序走訪
|
||
|
|
fn preOrder(comptime T: type, root: ?*inc.TreeNode(T)) !void {
|
||
|
|
if (root == null) return;
|
||
|
|
// 訪問優先順序：根節點 -> 左子樹 -> 右子樹
|
||
|
|
try list.append(root.?.val);
|
||
|
|
try preOrder(T, root.?.left);
|
||
|
|
try preOrder(T, root.?.right);
|
||
|
|
}
|
||
|
|
|
||
|
|
// 中序走訪
|
||
|
|
fn inOrder(comptime T: type, root: ?*inc.TreeNode(T)) !void {
|
||
|
|
if (root == null) return;
|
||
|
|
// 訪問優先順序：左子樹 -> 根節點 -> 右子樹
|
||
|
|
try inOrder(T, root.?.left);
|
||
|
|
try list.append(root.?.val);
|
||
|
|
try inOrder(T, root.?.right);
|
||
|
|
}
|
||
|
|
|
||
|
|
// 後序走訪
|
||
|
|
fn postOrder(comptime T: type, root: ?*inc.TreeNode(T)) !void {
|
||
|
|
if (root == null) return;
|
||
|
|
// 訪問優先順序：左子樹 -> 右子樹 -> 根節點
|
||
|
|
try postOrder(T, root.?.left);
|
||
|
|
try postOrder(T, root.?.right);
|
||
|
|
try list.append(root.?.val);
|
||
|
|
}
|
||
|
|
|
||
|
|
// Driver Code
|
||
|
|
pub fn main() !void {
|
||
|
|
// 初始化記憶體分配器
|
||
|
|
var mem_arena = std.heap.ArenaAllocator.init(std.heap.page_allocator);
|
||
|
|
defer mem_arena.deinit();
|
||
|
|
const mem_allocator = mem_arena.allocator();
|
||
|
|
|
||
|
|
// 初始化二元樹
|
||
|
|
// 這裡藉助了一個從陣列直接生成二元樹的函式
|
||
|
|
var nums = [_]i32{1, 2, 3, 4, 5, 6, 7};
|
||
|
|
var root = try inc.TreeUtil.arrToTree(i32, mem_allocator, &nums);
|
||
|
|
std.debug.print("初始化二元樹\n", .{});
|
||
|
|
try inc.PrintUtil.printTree(root, null, false);
|
||
|
|
|
||
|
|
// 前序走訪
|
||
|
|
list.clearRetainingCapacity();
|
||
|
|
try preOrder(i32, root);
|
||
|
|
std.debug.print("\n前序走訪的節點列印序列 = ", .{});
|
||
|
|
inc.PrintUtil.printList(i32, list);
|
||
|
|
|
||
|
|
// 中序走訪
|
||
|
|
list.clearRetainingCapacity();
|
||
|
|
try inOrder(i32, root);
|
||
|
|
std.debug.print("\n中序走訪的節點列印序列 = ", .{});
|
||
|
|
inc.PrintUtil.printList(i32, list);
|
||
|
|
|
||
|
|
// 後序走訪
|
||
|
|
list.clearRetainingCapacity();
|
||
|
|
try postOrder(i32, root);
|
||
|
|
std.debug.print("\n後續走訪的節點列印序列 = ", .{});
|
||
|
|
inc.PrintUtil.printList(i32, list);
|
||
|
|
|
||
|
|
_ = try std.io.getStdIn().reader().readByte();
|
||
|
|
}
|