Compilare: user.cpp: In function ‘bool apply_updates(int)’: user.cpp:50:44: warning: comparison between signed and unsigned integer expressions [-Wsign-compare] for ( i = 0 ; i < edge [ node ] . size() ; i ++ ) ^ user.cpp: In function ‘void read()’: user.cpp:29:37: warning: ignoring return value of ‘int fscanf(FILE*, const char*, ...)’, declared with attribute warn_unused_result [-Wunused-result] fscanf ( f , "%d %d" , &N , &M ); ^ user.cpp:34:52: warning: ignoring return value of ‘int fscanf(FILE*, const char*, ...)’, declared with attribute warn_unused_result [-Wunused-result] fscanf ( f , "%d %d %d" , &x , &y , &cost ); ^