add zig codes for Section 'Hash Map'

codes/zig/build.zig

@@ -160,6 +160,20 @@ pub fn build(b: *std.build.Builder) void {
         const run_step_array_stack = b.step("run_array_stack", "Run array_stack");
         run_step_array_stack.dependOn(&run_cmd_array_stack.step);      
 
+    // Section: "Hash Map"
+        // Source File: "chapter_hashing/hash_map.zig"
+        // Run Command: zig build run_hash_map
+        const exe_hash_map = b.addExecutable("hash_map", "chapter_hashing/hash_map.zig");
+        exe_hash_map.addPackagePath("include", "include/include.zig");
+        exe_hash_map.setTarget(target);
+        exe_hash_map.setBuildMode(mode);
+        exe_hash_map.install();
+        const run_cmd_hash_map = exe_hash_map.run();
+        run_cmd_hash_map.step.dependOn(b.getInstallStep());
+        if (b.args) |args| run_cmd_hash_map.addArgs(args);
+        const run_step_hash_map= b.step("run_hash_map", "Run hash_map");
+        run_step_hash_map.dependOn(&run_cmd_hash_map.step);
+
     // Section: "Bubble Sort"
         // Source File: "chapter_sorting/bubble_sort.zig"
         // Run Command: zig build run_bubble_sort

codes/zig/chapter_hashing/hash_map.zig

@@ -0,0 +1,55 @@
+// File: hash_map.zig
+// Created Time: 2023-01-13
+// Author: sjinzh (sjinzh@gmail.com)
+
+const std = @import("std");
+const inc = @import("include");
+
+// Driver Code
+pub fn main() !void {
+    // 初始化哈希表
+    var map = std.AutoHashMap(i32, []const u8).init(std.heap.page_allocator);
+    // 延迟释放内存
+    defer map.deinit();
+
+    // 添加操作
+    // 在哈希表中添加键值对 (key, value)
+    try map.put(12836, "小哈");
+    try map.put(15937, "小啰");
+    try map.put(16750, "小算");
+    try map.put(13276, "小法");
+    try map.put(10583, "小鸭");
+    std.debug.print("\n添加完成后，哈希表为\nKey -> Value\n", .{});
+    inc.PrintUtil.printHashMap(i32, []const u8, map);
+
+    // 查询操作
+    // 向哈希表输入键 key ，得到值 value
+    var name = map.get(15937).?;
+    std.debug.print("\n输入学号 15937 ，查询到姓名 {s}\n", .{name});
+
+    // 删除操作
+    // 在哈希表中删除键值对 (key, value)
+    _ = map.remove(10583);
+    std.debug.print("\n删除 10583 后，哈希表为\nKey -> Value\n", .{});
+    inc.PrintUtil.printHashMap(i32, []const u8, map);
+
+    // 遍历哈希表
+    std.debug.print("\n遍历键值对 Key->Value\n", .{});
+    inc.PrintUtil.printHashMap(i32, []const u8, map);
+
+    std.debug.print("\n单独遍历键 Key\n", .{});
+    var it = map.iterator();
+    while (it.next()) |kv| {
+        std.debug.print("{}\n", .{kv.key_ptr.*});
+    }
+
+    std.debug.print("\n单独遍历值 value\n", .{});
+    it = map.iterator();
+    while (it.next()) |kv| {
+        std.debug.print("{s}\n", .{kv.value_ptr.*});
+    }
+
+    const getchar = try std.io.getStdIn().reader().readByte();
+    _ = getchar;
+}
+

codes/zig/include/PrintUtil.zig

@@ -46,6 +46,16 @@ pub fn printLinkedList(comptime T: type, node: ?*ListNode(T)) !void {
     }
 }
 
+// Print a HashMap
+pub fn printHashMap(comptime TKey: type, comptime TValue: type, map: std.AutoHashMap(TKey, TValue)) void {
+    var it = map.iterator();
+    while (it.next()) |kv| {
+        var key = kv.key_ptr.*;
+        var value = kv.value_ptr.*;
+        std.debug.print("{} -> {s}\n", .{key, value});
+    }
+}
+
 // This tree printer is borrowed from TECHIE DELIGHT
 // https://www.techiedelight.com/c-program-print-binary-tree/
 const Trunk = struct {