037-046 completed

exercises/037_structs.zig

@@ -36,6 +36,7 @@ const Character = struct {
     role: Role,
     gold: u32,
     experience: u32,
+    health: u8,
 };
 
 pub fn main() void {
@@ -44,6 +45,7 @@ pub fn main() void {
         .role = Role.wizard,
         .gold = 20,
         .experience = 10,
+        .health = 100,
     };
 
     // Glorp gains some gold.

exercises/038_structs2.zig

@@ -43,6 +43,13 @@ pub fn main() void {
     // Feel free to run this program without adding Zump. What does
     // it do and why?
 
+    chars[1] = Character{
+        .role = Role.bard,
+        .gold = 10,
+        .health = 100,
+        .experience = 20,
+    };
+
     // Printing all RPG characters in a loop:
     for (chars, 0..) |c, num| {
         std.debug.print("Character {} - G:{} H:{} XP:{}\n", .{

exercises/039_pointers.zig

@@ -30,7 +30,7 @@ pub fn main() void {
 
     // Please make num2 equal 5 using num1_pointer!
     // (See the "cheatsheet" above for ideas.)
-    num2 = ???;
+    num2 = num1_pointer.*;
 
     std.debug.print("num1: {}, num2: {}\n", .{ num1, num2 });
 }

exercises/040_pointers2.zig

@@ -23,7 +23,7 @@ const std = @import("std");
 
 pub fn main() void {
     const a: u8 = 12;
-    const b: *u8 = &a; // fix this!
+    const b: *const u8 = &a; // fix this!
 
     std.debug.print("a: {}, b: {}\n", .{ a, b.* });
 }

exercises/041_pointers3.zig

@@ -31,7 +31,7 @@ pub fn main() void {
 
     // Please define pointer "p" so that it can point to EITHER foo or
     // bar AND change the value it points to!
-    ??? p: ??? = undefined;
+    var p: *u8 = undefined;
 
     p = &foo;
     p.* += 1;

exercises/042_pointers4.zig

@@ -37,5 +37,5 @@ pub fn main() void {
 // This function should take a reference to a u8 value and set it
 // to 5.
 fn makeFive(x: *u8) void {
-    ??? = 5; // fix me!
+    x.* = 5; // fix me!
 }

exercises/043_pointers5.zig

@@ -68,7 +68,7 @@ pub fn main() void {
 
     // FIX ME!
     // Please pass Glorp to printCharacter():
-    printCharacter(???);
+    printCharacter(&glorp);
 }
 
 // Note how this function's "c" parameter is a pointer to a Character struct.

exercises/044_quiz5.zig

@@ -19,12 +19,14 @@ const Elephant = struct {
 pub fn main() void {
     var elephantA = Elephant{ .letter = 'A' };
     // (Please add Elephant B here!)
+    var elephantB = Elephant{ .letter = 'B' };
     var elephantC = Elephant{ .letter = 'C' };
 
     // Link the elephants so that each tail "points" to the next elephant.
     // They make a circle: A->B->C->A...
     elephantA.tail = &elephantB;
     // (Please link Elephant B's tail to Elephant C here!)
+    elephantB.tail = &elephantC;
     elephantC.tail = &elephantA;
 
     visitElephants(&elephantA);

exercises/045_optionals.zig

@@ -29,7 +29,7 @@ pub fn main() void {
 
     // Please threaten the result so that answer is either the
     // integer value from deepThought() OR the number 42:
-    const answer: u8 = result;
+    const answer: u8 = result orelse 42;
 
     std.debug.print("The Ultimate Answer: {}.\n", .{answer});
 }

exercises/046_optionals2.zig

@@ -21,7 +21,7 @@ const std = @import("std");
 
 const Elephant = struct {
     letter: u8,
-    tail: *Elephant = null, // Hmm... tail needs something...
+    tail: ?*Elephant = null, // Hmm... tail needs something...
     visited: bool = false,
 };
 
@@ -51,7 +51,7 @@ fn visitElephants(first_elephant: *Elephant) void {
         // We should stop once we encounter a tail that
         // does NOT point to another element. What can
         // we put here to make that happen?
-        if (e.tail == null) ???;
+        if (e.tail == null) break;
 
         e = e.tail.?;
     }