iterators4 solution

exercises/18_iterators/iterators4.rs

@@ -1,9 +1,9 @@
-fn factorial(num: u64) -> u64 {
-    // Complete this function to return the factorial of num
+fn factorial(num: u8) -> u64 {
+    // TODO: Complete this function to return the factorial of `num`.
     // Do not use:
     // - early returns (using the `return` keyword explicitly)
     // Try not to use:
-    // - imperative style loops (for, while)
+    // - imperative style loops (for/while)
     // - additional variables
     // For an extra challenge, don't use:
     // - recursion
@@ -19,20 +19,20 @@ mod tests {
 
     #[test]
     fn factorial_of_0() {
-        assert_eq!(1, factorial(0));
+        assert_eq!(factorial(0), 1);
     }
 
     #[test]
     fn factorial_of_1() {
-        assert_eq!(1, factorial(1));
+        assert_eq!(factorial(1), 1);
     }
     #[test]
     fn factorial_of_2() {
-        assert_eq!(2, factorial(2));
+        assert_eq!(factorial(2), 2);
     }
 
     #[test]
     fn factorial_of_4() {
-        assert_eq!(24, factorial(4));
+        assert_eq!(factorial(4), 24);
     }
 }