class TrieNode {
        Map<Character, TrieNode> children = new HashMap<>();
        int count = 0;
    }

     class Result {
        public static List<Integer> contacts(List<List<String>> queries) {
            TrieNode root = new TrieNode();
            List<Integer> results = new ArrayList<>();

            for (List<String> query : queries) {
                String operation = query.get(0);
                String value = query.get(1);

                if (operation.equals("add")) {
                    addContact(root, value);
                } else if (operation.equals("find")) {
                    results.add(findPartial(root, value));
                }
            }

            return results;
        }

        private static void addContact(TrieNode root, String contact) {
            TrieNode current = root;
            for (char c : contact.toCharArray()) {
                current.children.putIfAbsent(c, new TrieNode());
                current = current.children.get(c);
                current.count++;
            }
        }

        private static int findPartial(TrieNode root, String prefix) {
            TrieNode current = root;
            for (char c : prefix.toCharArray()) {
                current = current.children.get(c);
                if (current == null) {
                    return 0;
                }
            }
            return current.count;
        }
    }