#include <iostream>
#include <string>
#include <unordered_set>

int main()
{
    std::ios::sync_with_stdio(false);
    std::size_t N;
    std::size_t res {0};
    std::cin >> N;
    std::string str;
    std::getline (std::cin, str);
    std::unordered_set<std::string> dictionary;
    while (N--) {
        std::getline (std::cin, str);
        if (dictionary.find(str) == std::cend(dictionary))
            dictionary.insert (str);
        else
            res++;
    }
    std::cout << res << std::endl;
}