Merge branch 'main' of https://codeberg.org/ziglings/exercises

Reviewed-on: https://codeberg.org/ziglings/exercises/pulls/95

build.zig

@@ -1128,7 +1128,7 @@ const exercises = [_]Exercise{
         .main_file = "107_files2.zig",
         .output =
         \\AAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAA
-        \\Successfully Read 18 byte: It's zigling time!
+        \\Successfully Read 18 bytes: It's zigling time!
         ,
     },
     .{

exercises/046_optionals2.zig

@@ -51,6 +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) break;
 
         e = e.tail.?;

exercises/059_integers.zig

@@ -20,9 +20,9 @@ const print = @import("std").debug.print;
 
 pub fn main() void {
     const zig = [_]u8{
-        0o131, // octal
-        0b1101000, // binary
-        0x66, // hex
+        0o132, // octal
+        0b1101001, // binary
+        0x67, // hex
     };
 
     print("{s} is cool.\n", .{zig});

exercises/060_floats.zig

@@ -43,7 +43,7 @@ pub fn main() void {
     //
     // We'll convert this weight from pound to kilograms at a
     // conversion of 0.453592kg to the pound.
-    const shuttle_weight: f16 = 0.453592 * 4480e6;
+    const shuttle_weight: f32 = 0.453592 * 4480e+3;
 
     // By default, float values are formatted in scientific
     // notation. Try experimenting with '{d}' and '{d:.3}' to see

exercises/061_coercions.zig

@@ -67,7 +67,7 @@ const print = @import("std").debug.print;
 pub fn main() void {
     var letter: u8 = 'A';
 
-    const my_letter:   ???   = &letter;
+    const my_letter: ?*[1]u8 = &letter;
     //               ^^^^^^^
     //           Your type here.
     // Must coerce from &letter (which is a *u8).

exercises/094_c_math.zig

@@ -13,7 +13,7 @@
 // How could we do that? A good method is to use the modulo function.
 // But if we write "765.2 % 360", it only works with float values
 // that are known at compile time.
-// In Zig, we would use %mod(a, b) instead.
+// In Zig, we would use @mod(a, b) instead.
 //
 // Let us now assume that we cannot do this in Zig, but only with
 // a C function from the standard library. In the library "math",

exercises/096_memory_allocation.zig

@@ -30,9 +30,9 @@
 //         std.debug.print("slice_ptr={*}\n", .{slice_ptr});
 //     }
 
-// Instead of a simple integer or a constant sized slice, this
-// program requires a slice to be allocated that is the same size as
-// an input array.
+// Instead of a simple integer or a slice with a constant size,
+// this program requires allocating a slice that is the same size
+// as an input array.
 
 // Given a series of numbers, take the running average. In other
 // words, each item N should contain the average of the last N

exercises/097_bit_manipulation.zig

@@ -1,5 +1,5 @@
 //
-// Bit manipulations is a very powerful tool just also from Zig.
+// Bit manipulation is a very powerful tool, also from Zig.
 // Since the dawn of the computer age, numerous algorithms have been
 // developed that solve tasks solely by moving, setting, or logically
 // combining bits.
@@ -8,10 +8,10 @@
 // functions where possible. And it is often possible with calculations
 // based on integers.
 //
-// Often it is not easy to understand at first glance what exactly these
+// At first glance, it is often not easy to understand what exactly these
 // algorithms do when only "numbers" in memory areas change outwardly.
-// But it must never be forgotten that the numbers only represent the
-// interpretation of the bit sequences.
+// However, it should never be forgotten that the numbers only represent
+// the interpretation of the bit sequences.
 //
 // Quasi the reversed case we have otherwise, namely that we represent
 // numbers in bit sequences.
@@ -21,7 +21,7 @@
 // Zig provides all the necessary functions to change the bits inside
 // a variable. It is distinguished whether the bit change leads to an
 // overflow or not. The details are in the Zig documentation in section
-// 10.1 "Table of Operators".
+// "Table of Operators".
 //
 // Here are some examples of how the bits of variables can be changed:
 //

exercises/098_bit_manipulation2.zig

@@ -1,5 +1,5 @@
 //
-// Another useful practice for bit manipulation is setting bits as flags.
+// Another useful application for bit manipulation is setting bits as flags.
 // This is especially useful when processing lists of something and storing
 // the states of the entries, e.g. a list of numbers and for each prime
 // number a flag is set.
@@ -19,9 +19,9 @@
 // For example, you could take an array of bool and set the value to 'true'
 // for each letter in the order of the alphabet (a=0; b=1; etc.) found in
 // the sentence. However, this is neither memory efficient nor particularly
-// fast. Instead we take a simpler way, very similar in principle, we define
-// a variable with at least 26 bits (e.g. u32) and also set the bit for each
-// letter found at the corresponding position.
+// fast. Instead we choose a simpler approach that is very similar in principle:
+// We define a variable with at least 26 bits (e.g. u32) and set the bit for
+// each letter that is found in the corresponding position.
 //
 // Zig provides functions for this in the standard library, but we prefer to
 // solve it without these extras, after all we want to learn something.
@@ -39,7 +39,7 @@ fn isPangram(str: []const u8) bool {
     // first we check if the string has at least 26 characters
     if (str.len < 26) return false;
 
-    // we uses a 32 bit variable of which we need 26 bits
+    // we use a 32 bit variable of which we need 26 bits
     var bits: u32 = 0;
 
     // loop about all characters in the string

exercises/099_formatting.zig

@@ -19,10 +19,10 @@
 //     https://github.com/ziglang/zig/blob/master/lib/std/fmt.zig#L29
 //
 // Zig already has a very nice selection of formatting options.
-// These can be used in different ways, but typically to convert
-// numerical values into various text representations. The
-// results can be used for direct output to a terminal or stored
-// for later use or written to a file. The latter is useful when
+// These can be used in different ways, but generally to convert
+// numerical values into various text representations. The results
+// can be used for direct output to a terminal or stored for
+// later use or written to a file. The latter is useful when
 // large amounts of data are to be processed by other programs.
 //
 // In Ziglings, we are concerned with the output to the console.

exercises/104_threading.zig

@@ -4,8 +4,8 @@
 // one possibility, namely asynchronous processes, in Exercises 84-91.
 //
 // However, the computing power of the processor is only distributed to
-// the started tasks, which always reaches its limits when pure computing
-// power is called up.
+// the started and running tasks, which always reaches its limits when
+// pure computing power is called up.
 //
 // For example, in blockchains based on proof of work, the miners have
 // to find a nonce for a certain character string so that the first m bits

exercises/105_threading2.zig

@@ -1,6 +1,6 @@
 //
-// Now that we are familiar with the principles of multi threading, we
-// boldly venture into a practical example from mathematics.
+// Now that we are familiar with the principles of multi-threading,
+// let's boldly venture into a practical example from mathematics.
 // We will determine the circle number PI with sufficient accuracy.
 //
 // There are different methods for this, and some of them are several
@@ -104,4 +104,4 @@ fn thread_pi(pi: *f64, begin: u64, end: u64) !void {
 // to such an extent that seconds become minutes during execution.
 //
 // And you should remove the formatting restriction in "print",
-// otherwise you will not be able to see the additional diggits.
+// otherwise you will not be able to see the additional digits.

exercises/106_files.zig

@@ -50,20 +50,20 @@ pub fn main() !void {
     // we try to open the file `zigling.txt`,
     // and propagate the error up if there are any errors
     const file: std.fs.File = try output_dir.createFile("zigling.txt", .{});
-    // it is a good habit to close a file after you are done with
-    // so that other program can read it and prevent data corruption
+    // it is a good habit to close a file after you are done with it
+    // so that other programs can read it and prevent data corruption
     // but here we are not yet done writing to the file
-    // if only there are a keyword in zig that
-    // allow you "defer" code execute to the end of scope...
+    // if only there were a keyword in zig that
+    // allows you "defer" code execute to the end of scope...
     file.close();
 
-    // !you are not allow to switch this two lines to before file closing line!
+    // !you are not allowed to switch these two lines above the file closing line!
     const byte_written = try file.write("It's zigling time!");
     std.debug.print("Successfully wrote {d} bytes.\n", .{byte_written});
 }
 // to check if you actually write to the file, you can either,
 // 1. open the file on your text editor, or
-// 2. print the content of the file in the console with command
+// 2. print the content of the file in the console with the following command
 //    >> cat ./output/zigling.txt
 //
 //
@@ -89,4 +89,4 @@ pub fn main() !void {
 //   - go to documentation of the struct `std.fs.Dir` here
 //     https://ziglang.org/documentation/master/std/#std.fs.Dir
 //       - can you find a function for opening a file? how about deleting a file?
-//       - what kind of option can you uses with those function?
+//       - what kind of options can you use with those functions?

exercises/107_files2.zig

@@ -5,15 +5,15 @@
 //      with content `It's zigling time!`(18 byte total)
 //
 // Now there no point in writing to a file if we don't read from it am I right?
-// let's wrote a program to read the content of the file that we just created.
+// let's write a program to read the content of the file that we just created.
 //
-// I am assuming you've created the appropriate files for this to work.
+// I am assuming that you've created the appropriate files for this to work.
 //
 // Alright, bud, lean in close here's the game plan.
 //    - First, we open the {project_root}/output/ directory
 //    - Secondly, we open file `zigling.txt` in that directory
-//    - then, we initalize an array of character with all letter 'A', and print it
-//    - Afte that, we read the content of the file to the array
+//    - then, we initalize an array of characters with all letter 'A', and print it
+//    - After that, we read the content of the file to the array
 //    - Finally, we print out the read content
 
 const std = @import("std");
@@ -31,22 +31,22 @@ pub fn main() !void {
     defer file.close();
 
     // initalize an array of u8 with all letter 'A'.
-    // we need to pick a size of the array, 64 seems like a good number.
+    // we need to pick the size of the array, 64 seems like a good number.
     // fix the initalization below
     var content = ['A']*64;
     // this should print out : `AAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAA`
     std.debug.print("{s}\n", .{content});
 
-    // okay, seem like threat of violence is not the answer in this case
+    // okay, seems like a threat of violence is not the answer in this case
     // can you go here to find a way to read the content ?
     // https://ziglang.org/documentation/master/std/#std.fs.File
-    // hint: you might find two answer that are both vaild in this case
-    const byte_read = zig_read_the_file_or_i_will_fight_you(&content);
+    // hint: you might find two answers that are both vaild in this case
+    const bytes_read = zig_read_the_file_or_i_will_fight_you(&content);
 
     // Woah, too screamy, I know you're excited for zigling time but tone it down a bit
     // Can you print only what we read from the file ?
-    std.debug.print("Successfully Read {d} byte: {s}\n", .{
-        byte_read,
+    std.debug.print("Successfully Read {d} bytes: {s}\n", .{
+        bytes_read,
         content, // change this line only
     });
 }

patches/patches/046_optionals2.patch

@@ -1,5 +1,5 @@
---- exercises/046_optionals2.zig	2023-10-03 22:15:22.122241138 +0200
-+++ answers/046_optionals2.zig	2023-10-05 20:04:07.049433424 +0200
+--- exercises/046_optionals2.zig	2024-05-10 23:11:25.796632478 +0200
++++ answers/046_optionals2.zig	2024-05-10 23:10:16.115335668 +0200
 @@ -21,7 +21,7 @@
  
  const Elephant = struct {
@@ -9,12 +9,11 @@
      visited: bool = false,
  };
  
-@@ -51,7 +51,7 @@
+@@ -51,6 +51,6 @@
          // 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.?;
+-        e = e.tail ???
++        e = e.tail orelse break;
+     }
  }

patches/patches/106_files.patch

@@ -1,5 +1,5 @@
---- exercises/106_files.zig	2024-03-27 16:52:05.660910200 +0800
-+++ answers/106_files.zig	2024-03-27 16:52:09.649422200 +0800
+--- exercises/106_files.zig	2024-05-05 00:48:25.808548611 +0200
++++ answers/106_files.zig	2024-05-05 01:00:40.742969819 +0200
 @@ -35,7 +35,7 @@
          // by doing nothing
          //
@@ -20,10 +20,10 @@
      // we try to open the file `zigling.txt`,
 @@ -55,7 +55,7 @@
      // but here we are not yet done writing to the file
-     // if only there are a keyword in zig that
-     // allow you "defer" code execute to the end of scope...
+     // if only there were a keyword in zig that
+     // allows you "defer" code execute to the end of scope...
 -    file.close();
 +    defer file.close();
  
-     // !you are not allow to switch this two lines to before file closing line!
+     // !you are not allowed to switch these two lines above the file closing line!
      const byte_written = try file.write("It's zigling time!");

patches/patches/107_files2.patch

@@ -1,8 +1,8 @@
---- exercises/107_files2.zig	2024-03-27 16:51:56.199719600 +0800
-+++ answers/107_files2.zig	2024-03-27 16:52:01.650935300 +0800
+--- exercises/107_files2.zig	2024-05-05 00:48:25.808548611 +0200
++++ answers/107_files2.zig	2024-05-05 01:14:03.866062288 +0200
 @@ -33,7 +33,7 @@
      // initalize an array of u8 with all letter 'A'.
-     // we need to pick a size of the array, 64 seems like a good number.
+     // we need to pick the size of the array, 64 seems like a good number.
      // fix the initalization below
 -    var content = ['A']*64;
 +    var content = [_]u8{'A'} ** 64;
@@ -12,15 +12,15 @@
 @@ -41,12 +41,12 @@
      // can you go here to find a way to read the content ?
      // https://ziglang.org/documentation/master/std/#std.fs.File
-     // hint: you might find two answer that are both vaild in this case
--    const byte_read = zig_read_the_file_or_i_will_fight_you(&content);
-+    const byte_read = try file.read(&content);
+     // hint: you might find two answers that are both vaild in this case
+-    const bytes_read = zig_read_the_file_or_i_will_fight_you(&content);
++    const bytes_read = try file.read(&content);
  
      // Woah, too screamy, I know you're excited for zigling time but tone it down a bit
      // Can you print only what we read from the file ?
-     std.debug.print("Successfully Read {d} byte: {s}\n", .{
-         byte_read,
+     std.debug.print("Successfully Read {d} bytes: {s}\n", .{
+         bytes_read,
 -        content, // change this line only
-+        content[0..byte_read], // change this line only
++        content[0..bytes_read], // change this line only
      });
  }