From a5a545259ac471152124da21d7362c45363fe1dc Mon Sep 17 00:00:00 2001
From: jacwil <jacwil014@gmail.com>
Date: Sat, 13 Jan 2024 20:36:35 -0800
Subject: [PATCH] Make the example more realistic

---
 build.zig                   |  2 +-
 exercises/076_sentinels.zig | 23 ++++++++++++-----------
 2 files changed, 13 insertions(+), 12 deletions(-)

diff --git a/build.zig b/build.zig
index 058adae..c4d274c 100644
--- a/build.zig
+++ b/build.zig
@@ -913,7 +913,7 @@ const exercises = [_]Exercise{
     },
     .{
         .main_file = "076_sentinels.zig",
-        .output = "Array:[ 1 2 3 0 5 6 ]. Many-item pointer:[ 1 2 3 ]. Array:[ 30 31 32 20 34 35 ]. Many-item pointer:[ 30 31 32 ].",
+        .output = "Array:[ 1 2 3 0 5 6 ]. Many-item pointer:[ 1 2 3 ]. Array:[ 5 4 3 ffff 1 0 ]. Many-item pointer:[ 5 4 3 ].",
     },
     .{
         .main_file = "077_sentinels2.zig",
diff --git a/exercises/076_sentinels.zig b/exercises/076_sentinels.zig
index c95b5da..5c1d3c9 100644
--- a/exercises/076_sentinels.zig
+++ b/exercises/076_sentinels.zig
@@ -49,21 +49,22 @@ pub fn main() void {
     const ptr: [*:0]u32 = &nums;
 
     // Just to show not everything must be zero-terminated, here
-    // is a space-terminated array of u8 values 👾:
-    var space = [_:' ']u8{ '0', '1', '2', '3', '4', '5' };
+    // is max-value termination (bits are all ones, which can be
+    // interpereted as a -1 for a signed number type):
+    var morenums = [_:0xFFFF]u16{ 5, 4, 3, 2, 1, 0 };
 
-    // And here's a space-terminated many-item pointer:
-    const spaceptr: [*:' ']u8 = &space;
+    // And here's a max-value terminated many-item pointer:
+    const morenumsptr: [*:0xFFFF]u16 = &morenums;
 
     // For fun, let's replace the value at position 3 with the
     // sentinel value. This seems kind of naughty.
     nums[3] = 0;
-    space[3] = ' ';
+    morenums[3] = 0xFFFF;
 
-    // Now we have a zero-terminated array, a space-terminated
-    // array, and a couple of many-item pointers that reference
-    // the same data: sequences of numbers that both end in and
-    // CONTAIN the sentinel value.
+    // Now we have a zero-terminated array, a max-value
+    // terminated array, and a couple of many-item pointers
+    // that reference the same data: sequences of numbers that
+    // both end in and CONTAIN the sentinel value.
     //
     // Attempting to loop through and print both of these should
     // demonstrate how they are similar and different.
@@ -73,8 +74,8 @@ pub fn main() void {
     // at the first sentinel value.)
     printSequence(nums);
     printSequence(ptr);
-    printSequence(space);
-    printSequence(spaceptr);
+    printSequence(morenums);
+    printSequence(morenumsptr);
 
     print("\n", .{});
 }