sync missing test for perfect-numbers

exercises/practice/perfect-numbers/.meta/example.cairo

@@ -15,17 +15,18 @@ pub fn classify(number: u64) -> Classification {
     let mut i = 2;
     let stop = sqrt(number);
 
-    while i < stop {
+    while i <= stop {
         if number % i == 0 {
-            let mut increment = i;
-            if i * i != number {
-                increment += number / i;
-            }
-            sum += increment;
+            sum += i + number / i;
         }
         i += 1;
     }
 
+    if stop * stop == number {
+        // When `number` is a square number, we added the same divisor twice inside the loop.
+        sum -= stop;
+    }
+
     if sum < number {
         Classification::Deficient
     } else if sum > number {
@@ -38,9 +39,10 @@ pub fn classify(number: u64) -> Classification {
 fn sqrt(radicand: u64) -> u64 {
     let mut candidate = 1;
     if radicand > 2 {
-        while (candidate * candidate) < radicand {
+        while (candidate * candidate) <= radicand {
             candidate += 1;
-        };
+        }
+        return candidate - 1;
     }
     candidate
 }

exercises/practice/perfect-numbers/.meta/tests.toml

@@ -27,6 +27,9 @@ description = "Abundant numbers -> Medium abundant number is classified correctl
 [ec7792e6-8786-449c-b005-ce6dd89a772b]
 description = "Abundant numbers -> Large abundant number is classified correctly"
 
+[05f15b93-849c-45e9-9c7d-1ea131ef7d10]
+description = "Abundant numbers -> Perfect square abundant number is classified correctly"
+
 [e610fdc7-2b6e-43c3-a51c-b70fb37413ba]
 description = "Deficient numbers -> Smallest prime deficient number is classified correctly"
 

exercises/practice/perfect-numbers/tests/perfect_numbers.cairo

@@ -39,6 +39,12 @@ fn large_abundant_number() {
     assert_eq!(classify(33550335), Classification::Abundant);
 }
 
+#[test]
+#[ignore]
+fn perfect_square_abundant_number_is_classified_correctly() {
+    assert_eq!(classify(196), Classification::Abundant);
+}
+
 // Deficient numbers
 
 #[test]