wip

exercises/18_iterators/iterators4.rs

@@ -3,7 +3,7 @@
 // Execute `rustlings hint iterators4` or use the `hint` watch subcommand for a
 // hint.
 
-// I AM NOT DONE
+use std::collections::btree_map::Range;
 
 pub fn factorial(num: u64) -> u64 {
     // Complete this function to return the factorial of num
@@ -15,6 +15,8 @@ pub fn factorial(num: u64) -> u64 {
     // For an extra challenge, don't use:
     // - recursion
     // Execute `rustlings hint iterators4` for hints.
+
+    (1..num + 1).into_iter().fold(1, |acc, x| acc * x)
 }
 
 #[cfg(test)]