Naive approach to Armstrong Number

armstrong-numbers/src/lib.rs

@@ -1,3 +1,8 @@
 pub fn is_armstrong_number(num: u32) -> bool {
-    unimplemented!("true if {} is an armstrong number", num)
+    let num_vec:Vec<u32> = num.to_string().chars().filter(|c| !c.is_numeric()).map(|c| c.to_digit(10).unwrap_or(0)).collect();
+    let mut total = 0;
+    for val in num_vec{
+        total += val.pow(2);
+    }
+    total == num
 }

armstrong-numbers/tests/armstrong-numbers.rs

@@ -6,49 +6,41 @@ fn test_zero_is_an_armstrong_number() {
 }
 
 #[test]
-#[ignore]
 fn test_single_digit_numbers_are_armstrong_numbers() {
     assert!(is_armstrong_number(5))
 }
 
 #[test]
-#[ignore]
 fn test_there_are_no_2_digit_armstrong_numbers() {
     assert!(!is_armstrong_number(10))
 }
 
 #[test]
-#[ignore]
 fn test_three_digit_armstrong_number() {
     assert!(is_armstrong_number(153))
 }
 
 #[test]
-#[ignore]
 fn test_three_digit_non_armstrong_number() {
     assert!(!is_armstrong_number(100))
 }
 
 #[test]
-#[ignore]
 fn test_four_digit_armstrong_number() {
     assert!(is_armstrong_number(9474))
 }
 
 #[test]
-#[ignore]
 fn test_four_digit_non_armstrong_number() {
     assert!(!is_armstrong_number(9475))
 }
 
 #[test]
-#[ignore]
 fn test_seven_digit_armstrong_number() {
     assert!(is_armstrong_number(9_926_315))
 }
 
 #[test]
-#[ignore]
 fn test_seven_digit_non_armstrong_number() {
     assert!(!is_armstrong_number(9_926_316))
 }