#include <iostream>

int main(int argc, const char *argv[])
{
    if(argc < 2)
    {
        return -1;
    }

    uint16_t line = std::stoi(argv[1]);

    uint16_t address = (line >> 1)*0x50 + (((line & 0x01) == 1)? 0x2000: 0x00);

    std::cout << std::showbase << std::hex << address << std::endl;

    return 0;
}