X-Git-Url: https://git.ralfj.de/rust-101.git/blobdiff_plain/9f6c55ebcab2e1d3073e8bb6c8c910d0116efee4..7c63fce3ed1474437f62a5f14cbd9fa398ec9abe:/workspace/src/part08.rs
diff --git a/workspace/src/part08.rs b/workspace/src/part08.rs
index 2d3b5d8..0118906 100644
--- a/workspace/src/part08.rs
+++ b/workspace/src/part08.rs
@@ -7,15 +7,13 @@ use part05::BigInt;
// So, let us write a function to "add with carry", and give it the appropriate type. Notice Rust's native support for pairs.
fn overflowing_add(a: u64, b: u64, carry: bool) -> (u64, bool) {
- let sum = u64::wrapping_add(a, b);
+ let sum = a.wrapping_add(b);
// If an overflow happened, then the sum will be smaller than *both* summands. Without an overflow, of course, it will be
// at least as large as both of them. So, let's just pick one and check.
if sum >= a {
// The addition did not overflow.
// **Exercise 08.1**: Write the code to handle adding the carry in this case.
- let sum_total = u64::wrapping_add(sum, if carry { 1 } else { 0 }); /*@@*/
- let had_overflow = sum_total < sum; /*@@*/
- (sum_total, had_overflow) /*@@*/
+ unimplemented!()
} else {
// Otherwise, the addition *did* overflow. It is impossible for the addition of the carry
// to overflow again, as we are just adding 0 or 1.
@@ -54,10 +52,7 @@ impl ops::Add for BigInt {
unimplemented!()
}
// **Exercise 08.2**: Handle the final `carry`, and return the sum.
- if carry { /*@@*/
- result_vec.push(1); /*@@*/
- } /*@@*/
- BigInt { data: result_vec } /*@@*/
+ unimplemented!()
}
}
@@ -81,7 +76,9 @@ impl<'a, 'b> ops::Add<&'a BigInt> for &'b BigInt {
// Rust calls a bunch of definitions that are grouped together a *module*. You can put the tests in a submodule as follows.
#[cfg(test)]
mod tests {
- #[test]
+ use part05::BigInt;
+
+ /*#[test]*/
fn test_add() {
let b1 = BigInt::new(1 << 32);
let b2 = BigInt::from_vec(vec![0, 1]);