diff --git a/codes/zig/build.zig b/codes/zig/build.zig index 4fae68ef..5a97289d 100644 --- a/codes/zig/build.zig +++ b/codes/zig/build.zig @@ -174,6 +174,20 @@ pub fn build(b: *std.build.Builder) void { const run_step_hash_map= b.step("run_hash_map", "Run hash_map"); run_step_hash_map.dependOn(&run_cmd_hash_map.step); + // Section: "Heap" + // Source File: "chapter_heap/heap.zig" + // Run Command: zig build run_heap + const exe_heap = b.addExecutable("heap", "chapter_heap/heap.zig"); + exe_heap.addPackagePath("include", "include/include.zig"); + exe_heap.setTarget(target); + exe_heap.setBuildMode(mode); + exe_heap.install(); + const run_cmd_heap = exe_heap.run(); + run_cmd_heap.step.dependOn(b.getInstallStep()); + if (b.args) |args| run_cmd_heap.addArgs(args); + const run_step_heap = b.step("run_heap", "Run heap"); + run_step_heap.dependOn(&run_cmd_heap.step); + // Section: "Linear Search" // Source File: "chapter_searching/linear_search.zig" // Run Command: zig build run_linear_search diff --git a/codes/zig/chapter_heap/heap.zig b/codes/zig/chapter_heap/heap.zig new file mode 100644 index 00000000..02e4ce8f --- /dev/null +++ b/codes/zig/chapter_heap/heap.zig @@ -0,0 +1,85 @@ +// File: heap.zig +// Created Time: 2023-01-14 +// Author: sjinzh (sjinzh@gmail.com) + +const std = @import("std"); +const inc = @import("include"); + +fn lessThan(context: void, a: i32, b: i32) std.math.Order { + _ = context; + return std.math.order(a, b); +} + +fn greaterThan(context: void, a: i32, b: i32) std.math.Order { + return lessThan(context, a, b).invert(); +} + +fn testPush(comptime T: type, mem_allocator: std.mem.Allocator, heap_push: anytype, val: T) !void { + var heap = heap_push; + try heap.add(val); //元素入堆 + std.debug.print("\n元素 {} 入堆后\n", .{val}); + try inc.PrintUtil.printHeap(T, mem_allocator, heap); +} + +fn testPop(comptime T: type, mem_allocator: std.mem.Allocator, heap_pop: anytype) !void { + var val = heap_pop.remove(); //堆顶元素出堆 + std.debug.print("\n堆顶元素 {} 出堆后\n", .{val}); + try inc.PrintUtil.printHeap(T, mem_allocator, heap_pop); +} + +// Driver Code +pub fn main() !void { + // 初始化内存分配器 + var mem_arena = std.heap.ArenaAllocator.init(std.heap.page_allocator); + // 延迟释放内存 + defer mem_arena.deinit(); + const mem_allocator = mem_arena.allocator(); + + // 初始化堆 + // 初始化小顶堆 + const PQlt = std.PriorityQueue(i32, void, lessThan); + var minHeap = PQlt.init(std.heap.page_allocator, {}); + defer minHeap.deinit(); + // 初始化大顶堆 + const PQgt = std.PriorityQueue(i32, void, greaterThan); + var maxHeap = PQgt.init(std.heap.page_allocator, {}); + defer maxHeap.deinit(); + + std.debug.print("\n以下测试样例为大顶堆", .{}); + + // 元素入堆 + try testPush(i32, mem_allocator, &maxHeap, 1); + try testPush(i32, mem_allocator, &maxHeap, 3); + try testPush(i32, mem_allocator, &maxHeap, 2); + try testPush(i32, mem_allocator, &maxHeap, 5); + try testPush(i32, mem_allocator, &maxHeap, 4); + + // 获取堆顶元素 + var peek = maxHeap.peek().?; + std.debug.print("\n堆顶元素为 {}\n", .{peek}); + + // 堆顶元素出堆 + try testPop(i32, mem_allocator, &maxHeap); + try testPop(i32, mem_allocator, &maxHeap); + try testPop(i32, mem_allocator, &maxHeap); + try testPop(i32, mem_allocator, &maxHeap); + try testPop(i32, mem_allocator, &maxHeap); + + // 获取堆的大小 + var size = maxHeap.len; + std.debug.print("\n堆元素数量为 {}", .{size}); + + // 判断堆是否为空 + var isEmpty = if (maxHeap.len == 0) true else false; + std.debug.print("\n堆是否为空 {}\n", .{isEmpty}); + + // 输入列表并建堆 + // 时间复杂度为 O(n) ，而非 O(nlogn) + try minHeap.addSlice(&[_]i32{ 1, 3, 2, 5, 4 }); + std.debug.print("\n输入列表并建立小顶堆后\n", .{}); + try inc.PrintUtil.printHeap(i32, mem_allocator, minHeap); + + const getchar = try std.io.getStdIn().reader().readByte(); + _ = getchar; +} + diff --git a/codes/zig/include/PrintUtil.zig b/codes/zig/include/PrintUtil.zig index 2ef9047c..d126acb3 100644 --- a/codes/zig/include/PrintUtil.zig +++ b/codes/zig/include/PrintUtil.zig @@ -3,8 +3,10 @@ // Author: sjinzh (sjinzh@gmail.com) const std = @import("std"); -const ListNode = @import("ListNode.zig").ListNode; -const TreeNode = @import("TreeNode.zig").TreeNode; +pub const ListUtil = @import("ListNode.zig"); +pub const ListNode = ListUtil.ListNode; +pub const TreeUtil = @import("TreeNode.zig"); +pub const TreeNode = TreeUtil.TreeNode; // Print an array pub fn printArray(comptime T: type, nums: []T) void { @@ -56,6 +58,17 @@ pub fn printHashMap(comptime TKey: type, comptime TValue: type, map: std.AutoHas } } +// print a heap (PriorityQueue) +pub fn printHeap(comptime T: type, mem_allocator: std.mem.Allocator, queue: anytype) !void { + var arr = queue.items; + var len = queue.len; + std.debug.print("堆的数组表示：", .{}); + printArray(T, arr[0..len]); + std.debug.print("\n堆的树状表示：\n", .{}); + var root = try TreeUtil.arrToTree(T, mem_allocator, arr[0..len]); + try printTree(root, null, false); +} + // This tree printer is borrowed from TECHIE DELIGHT // https://www.techiedelight.com/c-program-print-binary-tree/ const Trunk = struct { diff --git a/codes/zig/include/TreeNode.zig b/codes/zig/include/TreeNode.zig index 0c6bbf73..7c1e2ad2 100644 --- a/codes/zig/include/TreeNode.zig +++ b/codes/zig/include/TreeNode.zig @@ -21,4 +21,40 @@ pub fn TreeNode(comptime T: type) type { self.right = null; } }; +} + +// Generate a binary tree with an array +pub fn arrToTree(comptime T: type, mem_allocator: std.mem.Allocator, list: []T) !?*TreeNode(T) { + if (list.len == 0) return null; + var root = try mem_allocator.create(TreeNode(T)); + root.init(list[0]); + + const TailQueue = std.TailQueue(?*TreeNode(T)); + const TailQueueNode = std.TailQueue(?*TreeNode(T)).Node; + var que = TailQueue{}; + var node_root = TailQueueNode{ .data = root }; + que.append(&node_root); + var index: usize = 0; + while (que.len > 0) { + var node = que.popFirst(); + index += 1; + if (index >= list.len) break; + if (index < list.len) { + var tmp = try mem_allocator.create(TreeNode(T)); + tmp.init(list[index]); + node.?.data.?.left = tmp; + var a = TailQueueNode{ .data = node.?.data.?.left }; + que.append(&a); + } + index += 1; + if (index >= list.len) break; + if (index < list.len) { + var tmp = try mem_allocator.create(TreeNode(T)); + tmp.init(list[index]); + node.?.data.?.right = tmp; + var a = TailQueueNode{ .data = node.?.data.?.right }; + que.append(&a); + } + } + return root; } \ No newline at end of file