From: Ralf Jung <post@ralfj.de>
Date: Tue, 23 Jun 2015 13:23:17 +0000 (+0200)
Subject: some more exercises
X-Git-Url: https://git.ralfj.de/rust-101.git/commitdiff_plain/f9bb29fcf0e25966dddd1dca29d70d392a5dfdca?ds=sidebyside

some more exercises
---

diff --git a/solutions/src/lib.rs b/solutions/src/lib.rs
index 8f8d148..aff442c 100644
--- a/solutions/src/lib.rs
+++ b/solutions/src/lib.rs
@@ -1 +1,2 @@
 pub mod bigint;
+pub mod vec_min;
diff --git a/src/part01.rs b/src/part01.rs
index bff079b..05696a5 100644
--- a/src/part01.rs
+++ b/src/part01.rs
@@ -89,9 +89,8 @@ pub fn main() {
 // You will have to replace `part00` by `part01` in the `main` function in
 // `main.rs` to run this code.
 
-// **Exercise 01.1**: Write a funtion `vec_avg` that computes the average value of a `Vec<i32>` (rounded down to
-// the next integer).
-// 
-// *Hint*: `vec.len() as i32` returns the length of a vector `vec` as signed integer.
+// **Exercise 01.1**: Write a funtion `vec_sum` that computes the sum of all values of a `Vec<i32>`.
+
+// **Exercise 01.2**: Write a function `vec_print` that takes a vector and prints all its elements.
 
 // [index](main.html) | [previous](part00.html) | [next](part02.html)
diff --git a/src/part02.rs b/src/part02.rs
index 12faed8..57dc83e 100644
--- a/src/part02.rs
+++ b/src/part02.rs
@@ -3,10 +3,9 @@
 
 use std;
 
-// Let us for a moment reconsider the type `NumberOrNothing`. Isn't it a bit
-// annoying that we had to hard-code the type `i32` in there? What if tomorrow,
-// we want a `CharOrNothing`, and later a `FloatOrNothing`? Certainly we don't
-// want to re-write the type and all its inherent methods.
+// Let us for a moment reconsider the type `NumberOrNothing`. Isn't it a bit annoying that we
+// had to hard-code the type `i32` in there? What if tomorrow, we want a `CharOrNothing`, and
+// later a `FloatOrNothing`? Certainly we don't want to re-write the type and all its inherent methods.
 
 // ## Generic datatypes
 
@@ -24,9 +23,8 @@ pub use self::SomethingOrNothing::*;
 // `SomethingOrNothing<i32>` to get back our `NumberOrNothing`.
 type NumberOrNothing = SomethingOrNothing<i32>;
 // However, we can also write `SomethingOrNothing<bool>` or even `SomethingOrNothing<SomethingOrNothing<i32>>`.
-// In fact, such a type is so useful that it is already present in the standard
-// library: It's called an *option type*, written `Option<T>`.
-// Go check out its [documentation](http://doc.rust-lang.org/stable/std/option/index.html)!
+// In fact, such a type is so useful that it is already present in the standard library: It's called an
+// *option type*, written `Option<T>`. Go check out its [documentation](http://doc.rust-lang.org/stable/std/option/index.html)!
 // (And don't worry, there's indeed lots of material mentioned there that we did not cover yet.)
 
 // ## Generic `impl`, Static functions
@@ -146,4 +144,7 @@ pub fn main() {
 
 // If this printed `3`, then you generic `vec_min` is working! So get ready for the next part.
 
+// **Exercise 02.2**: Change your program such that it computes the minimum ofa `Vec<f32>` (where `f32` is the type
+// of 32-bit floating-point numbers). You should not change `vec_min` in any way, obviously!
+
 // [index](main.html) | [previous](part01.html) | [next](part03.html)
diff --git a/src/part03.rs b/src/part03.rs
index 0e7db1d..fa82eb7 100644
--- a/src/part03.rs
+++ b/src/part03.rs
@@ -108,4 +108,7 @@ impl<T: Print> SomethingOrNothing<T> {
     }
 }
 
+// **Exercise 03.2**: Building on exercise 02.2, implement all the things you need on `f32` to make your
+// program work with floating-point numbers.
+
 // [index](main.html) | [previous](part02.html) | [next](part04.html)