Implemented fn square()

hw1/task2/src/lib.rs

@@ -1,8 +1,8 @@
 pub fn square(n: u32) -> u64 {
-    unimplemented!()
+    println!(n)
+    n * n
 }
 
 
 pub fn total() -> u64 {
-    unimplemented!();
 }