Compilare: main.cpp: In function 'void dfs(int)': main.cpp:158:8: warning: statement has no effect [-Wunused-value] main.cpp:130:20: #define debug(...) (__VA_ARGS__) ~~~~~~~~~~~~~ main.cpp:158:8: debug(nod); main.cpp:130:21: note: in definition of macro 'debug' #define debug(...) (__VA_ARGS__) ^~~~~~~~~~~ main.cpp: In function 'int32_t main()': main.cpp:180:37: warning: ignoring return value of 'FILE* freopen(const char*, const char*, FILE*)', declared with attribute warn_unused_result [-Wunused-result] freopen(PROB_NAME".in", "r", stdin); ^ main.cpp:181:39: warning: ignoring return value of 'FILE* freopen(const char*, const char*, FILE*)', declared with attribute warn_unused_result [-Wunused-result] freopen(PROB_NAME".out", "w", stdout); ^