Compilare: main.cpp: In function 'int main()': main.cpp:79:36: warning: ignoring return value of 'FILE* freopen(const char*, const char*, FILE*)', declared with attribute warn_unused_result [-Wunused-result] freopen ("flooow.in", "r", stdin); ^ main.cpp:80:38: warning: ignoring return value of 'FILE* freopen(const char*, const char*, FILE*)', declared with attribute warn_unused_result [-Wunused-result] freopen ("flooow.out", "w", stdout); ^ main.cpp: In function 'char advance()': main.cpp:16:34: warning: ignoring return value of 'size_t fread(void*, size_t, size_t, FILE*)', declared with attribute warn_unused_result [-Wunused-result] fread(buffer, 1, SIZE, stdin); ^ main.cpp: In function 'int main()': main.cpp:73:44: warning: 'sol' may be used uninitialized in this function [-Wmaybe-uninitialized] return get_buckets (sol).first + 1LL * k * sol; ~~~~~~~~^~~~~ main.cpp:58:20: note: 'sol' was declared here int st, dr, mij, sol; ^~~