Add .reset() term for smart pointers in C++

content/cpp/concepts/pointers/terms/reset/reset.md

@@ -0,0 +1,102 @@
+---
+Title: '.reset()'
+Description: 'Releases ownership of the managed object and optionally takes ownership of a new object.'
+Subjects:
+  - 'Code Foundations'
+  - 'Computer Science'
+Tags:
+  - 'Containers'
+  - 'Pointers'
+CatalogContent:
+  - 'learn-c++'
+  - 'paths/computer-science'
+---
+
+The **`.reset()`** method is used with smart pointers in C++ (such as `std::unique_ptr` and `std::shared_ptr`). It releases ownership of the currently managed object (deleting it if this is the last owner) and optionally takes ownership of a new object passed as a raw pointer.
+
+This method safely manages dynamic memory by deleting the previously managed object (if any), thereby helping to prevent memory leaks.
+
+## Syntax
+
+```pseudo
+ptr.reset();              // Releases ownership and deletes the managed object
+ptr.reset(raw_ptr);       // Releases current object and takes ownership of raw_ptr
+```
+
+## Example
+
+This example demonstrates how `.reset()` releases ownership of the managed object, deletes it, and sets the pointer to null:
+
+```cpp
+#include <iostream>
+#include <memory>
+
+int main() {
+  std::unique_ptr<int> ptr(new int(42));
+  std::cout << "Value before reset: " << *ptr << std::endl;
+
+  ptr.reset(); // Releases ownership and deletes the managed object
+
+  if (!ptr) {
+    std::cout << "Pointer is null after reset." << std::endl;
+  }
+  return 0;
+}
+```
+
+The output of this code is:
+
+```shell
+Value before reset: 42
+Pointer is null after reset.
+```
+
+In this example:
+
+- A `std::unique_ptr` manages an `int` with a value of 42.
+- After calling `.reset()`, the managed object is deleted and the pointer becomes null.
+- The check `if (!ptr)` confirms the pointer was successfully reset.
+
+## Codebyte Example
+
+Run the following example to understand how the `.reset()` method works:
+
+```codebyte/cpp
+#include <iostream>
+#include <memory>
+#include <string>
+
+class TV {
+public:
+  TV(std::string brand) : brand_(brand) {
+    std::cout << brand_ << " TV is turned ON.\n";
+  }
+  ~TV() {
+    std::cout << brand_ << " TV is turned OFF.\n";
+  }
+  void watch() const {
+    std::cout << "Watching " << brand_ << " TV.\n";
+  }
+
+private:
+  std::string brand_;
+};
+
+int main() {
+  std::unique_ptr<TV> remote(new TV("Samsung"));  // Remote controls Samsung TV
+  remote->watch();
+
+  // Replace old TV with a new LG TV
+  remote.reset(new TV("LG"));  // Old TV turned off, now controlling LG TV
+  remote->watch();
+
+  // Put down the remote, no TV controlled now
+  remote.reset();  // LG TV turned off, remote controls nothing
+
+  if (!remote) {
+    std::cout << "Remote controls no TV now.\n";
+  }
+
+  return 0;
+}
+```