Fix overflow in checksum

1 files changed, 2 insertions, 1 deletions

diff --git a/src/main.rs b/src/main.rs
index 3aeb2e7..5b44958 100644
--- a/src/main.rs
+++ b/src/main.rs
@@ -49,7 +49,8 @@ fn main() {
         .array_chunks::<4>()
         .map(|bytes| u32::from_be_bytes(bytes))
         // Subtract expected as we're supposed to compute it with that blanked
-        .fold(0u32, |a,b| a.overflowing_add(b).0) - exp_checksum;
+        .fold(0u32, |a,b| a.overflowing_add(b).0)
+        .overflowing_sub(exp_checksum).0;
 
     if file_data.len() % 4 != 0 {
         panic!("Invalid checksum: Uneven number of bytes");