How is a new element added to the HashMap data structure?

In the data structure HashMap, adding a new element occurs as follows:

1. The hash code of the key is computed using the hashCode() method.
2. Based on the hash code, the index of the bucket in the array is determined, where the element will be stored.
3. If there are no elements in this bucket, a new entry with the key and value is created.
4. If the bucket already contains elements (collision), a traversal of the linked list or tree (in newer Java versions) occurs to check if the key already exists.
   • If the key is found, the value is updated.
   • If the key is not found, a new element is added to the structure (at the end of the list or in the tree).

Example of adding an element to HashMap in Java:

HashMap<String, Integer> map = new HashMap<>();
map.put("key", 42); // adding a key-value pair

Thus, adding a new element involves computing the hash, finding the bucket, and inserting or updating the record.