[Term Entry] C++ Unordered-sets: bucket_size() #8127

content/cpp/concepts/unordered-set/terms/bucket-size/bucket-size.md

@@ -0,0 +1,97 @@
+---
+Title: 'bucket_size()'
+Description: 'Returns the number of elements stored in a specific bucket of an unordered set.'
+Subjects:
+  - 'Code Foundations'
+  - 'Computer Science'
+Tags:
+  - 'Containers'
+  - 'Sets'
+  - 'STL'
+CatalogContent:
+  - 'learn-c-plus-plus'
+  - 'paths/computer-science'
+---
+
+The **`bucket_size()`** method returns the number of elements stored in a specific bucket of an [`unordered_set`](https://www.codecademy.com/resources/docs/cpp/unordered-set). An `unordered_set` stores elements in a [hash table](https://www.codecademy.com/resources/docs/general/data-structures/hash-table), where values are distributed into buckets based on their hash. This method helps inspect bucket distribution and understanding hash collisions.
+
+## Syntax
+
+```pseudo
+unordered_set_name.bucket_size(n)
+```
+
+**Parameters:**
+
+`n`: The bucket number to query. This value must be less than the total number of buckets returned by `bucket_count()`. It is of type `size_type`, which is an unsigned integral type.
+
+**Return value:**
+
+The `bucket_size()` method returns the number of elements in bucket `n` as an unsigned integer of type `size_type`.
+
+## Example
+
+This example shows how to inspect how elements are distributed across buckets in an `unordered_set`:
+
+```cpp
+#include <iostream>
+#include <unordered_set>
+
+using namespace std;
+
+int main() {
+  unordered_set<int> numbers = {10, 20, 30, 40, 50};
+
+  size_t totalBuckets = numbers.bucket_count();
+  cout << "Total buckets: " << totalBuckets << "\n";
+
+  for (size_t i = 0; i < totalBuckets; i++) {
+    cout << "Bucket " << i
+         << " has " << numbers.bucket_size(i)
+         << " elements\n";
+  }
+
+  return 0;
+}
+```
+
+This example results in the following output:
+
+```shell
+Total buckets: 5
+Bucket 0 has 5 elements
+Bucket 1 has 0 elements
+Bucket 2 has 0 elements
+Bucket 3 has 0 elements
+Bucket 4 has 0 elements
+```
+
+This output displays the number of elements assigned to each bucket. Some buckets may be empty, while others may contain multiple elements depending on the hash distribution.
+
+## Codebyte Example
+
+This example demonstrates using `bucket_size()` to detect hash collisions by finding buckets that contain more than one element:
+
+```codebyte/cpp
+#include <iostream>
+#include <unordered_set>
+
+using namespace std;
+
+int main() {
+  unordered_set<int> values = {1, 2, 3, 4, 5, 6, 7, 8};
+
+  size_t totalBuckets = values.bucket_count();
+  cout << "Buckets with collisions:\n";
+
+  for (size_t i = 0; i < totalBuckets; i++) {
+    if (values.bucket_size(i) > 1) {
+      cout << "Bucket " << i
+           << " has " << values.bucket_size(i)
+           << " elements\n";
+    }
+  }
+
+  return 0;
+}
+```