Compilare: main.cpp:108:0: warning: "dbg" redefined #define dbg(x...) main.cpp:101:0: note: this is the location of the previous definition #define dbg(x...) pr("[", #x, "] = ["), pc(x); main.cpp: In function 'int main()': main.cpp:116:36: warning: ignoring return value of 'FILE* freopen(const char*, const char*, FILE*)', declared with attribute warn_unused_result [-Wunused-result] freopen("cover.in", "r", stdin); ^ main.cpp:117:38: warning: ignoring return value of 'FILE* freopen(const char*, const char*, FILE*)', declared with attribute warn_unused_result [-Wunused-result] freopen("cover.out", "w", stdout); ^