Compilare: user.cpp: In function ‘int main()’: user.cpp:95:46: warning: ignoring return value of ‘FILE* freopen(const char*, const char*, FILE*)’, declared with attribute warn_unused_result [-Wunused-result] freopen ("cumainilecurate.out", "w", stdout); ^ user.cpp: In constructor ‘InputReader::InputReader(const char*)’: user.cpp:16:47: warning: ignoring return value of ‘size_t fread(void*, size_t, size_t, FILE*)’, declared with attribute warn_unused_result [-Wunused-result] fread(buffer, SIZE, 1, input_file); ^ user.cpp: In member function ‘void InputReader::advance()’: user.cpp:38:51: warning: ignoring return value of ‘size_t fread(void*, size_t, size_t, FILE*)’, declared with attribute warn_unused_result [-Wunused-result] fread(buffer, SIZE, 1, input_file); ^ user.cpp: In function ‘int main()’: user.cpp:73:18: warning: iteration 399u invokes undefined behavior [-Waggressive-loop-optimizations] st[i] = 0; ^ user.cpp:72:5: note: containing loop for (int i = 1; i <= v[ll][0]; ++i) ^