#ifdef DEBUG
    #define LOCAL_INPUT_FILE
#else
    #define USE_FILE_IO
#endif

#ifdef USE_FILE_IO
    #define INPUT_FILE "input.txt"
    #define OUTPUT_FILE "output.txt"
    #define cin ____cin
    #define cout ____cout
    ifstream cin(INPUT_FILE);
    ofstream cout(OUTPUT_FILE);
#else
    #ifdef LOCAL_INPUT_FILE
        #define cin ____cin
        ifstream cin("input.txt");
    #endif
#endif