Compilare: main.cpp: In function 'int get_dist(int, int)': main.cpp:71:9: warning: variable 'dx' set but not used [-Wunused-but-set-variable] int dx , dy ; ^~ main.cpp:71:14: warning: variable 'dy' set but not used [-Wunused-but-set-variable] int dx , dy ; ^~ main.cpp: In function 'void solve()': main.cpp:260:26: warning: comparison between signed and unsigned integer expressions [-Wsign-compare] while ( ord.size ( ) < ( n + 3 ) ) { ord.push_back ( 0 ) ; } ~~~~~~~~~~~~~^~~~~~~~~~~ main.cpp: In function 'void input()': main.cpp:239:42: warning: ignoring return value of 'int scanf(const char*, ...)', declared with attribute warn_unused_result [-Wunused-result] scanf ( "%d%d" , &output_type , &n ) ; ^ main.cpp:243:43: warning: ignoring return value of 'int scanf(const char*, ...)', declared with attribute warn_unused_result [-Wunused-result] scanf ( "%d%d%d" , &x , &y , &z ) ; ^ main.cpp:250:43: warning: ignoring return value of 'int scanf(const char*, ...)', declared with attribute warn_unused_result [-Wunused-result] scanf ( "%d%d%d" , &x , &y , &z ) ; ^ main.cpp: In function 'int main()': main.cpp:280:44: warning: ignoring return value of 'FILE* freopen(const char*, const char*, FILE*)', declared with attribute warn_unused_result [-Wunused-result] freopen ( "trenbus.in" , "r" , stdin ) ; ^