Fix typo

Signed-off-by: Hengqi Chen <chenhengqi@outlook.com>
diff --git a/book/src/using-bitfields.md b/book/src/using-bitfields.md
index c6d2c7e..41e07ad 100644
--- a/book/src/using-bitfields.md
+++ b/book/src/using-bitfields.md
@@ -85,5 +85,5 @@
 This will print out
 
 ```text
-StructWithBitfields: a:1, b:0, c:2
+StructWithBitfields: a:0, b:0, c:0
 ```