Compilare: main.cpp:104:0: warning: "dbg" redefined #define dbg(x...) main.cpp:97:0: note: this is the location of the previous definition #define dbg(x...) pr("[", #x, "] = ["), pc(x); main.cpp: In function 'int main()': main.cpp:123:32: warning: ignoring return value of 'FILE* freopen(const char*, const char*, FILE*)', declared with attribute warn_unused_result [-Wunused-result] freopen("a.in", "r", stdin); ^