fix `zig build` error when '.progress.txt' contains newline

1 files changed, 2 insertions, 1 deletions

diff --git a/build.zig b/build.zig
index 0ad2a1e..c3b2a43 100644
--- a/build.zig
+++ b/build.zig
@@ -278,7 +278,8 @@ pub fn build(b: *Build) !void {
             return error.UnexpectedEOF;
         }
 
-        starting_exercise = try std.fmt.parseInt(u32, contents, 10);
+        const trimmed_contents = std.mem.trim(u8, contents, "\r\n");
+        starting_exercise = try std.fmt.parseInt(u32, trimmed_contents, 10);
     } else |err| {
         switch (err) {
             std.Io.File.OpenError.FileNotFound => {