done with basic calc

exercises/02_basic_calculator/03_if_else/src/lib.rs

@@ -2,7 +2,13 @@
 /// `13` if `n` is divisible by `3`,
 /// `17` otherwise.
 fn magic_number(n: u32) -> u32 {
-    todo!()
+    if n % 2 == 0 {
+        return 12;
+    } else if n % 3 == 0 {
+        return 13;
+    } else {
+        return 17;
+    }
 }
 
 #[cfg(test)]