Mã chấm: 268069

Main.cc: In function ‘int main()’:
Main.cc:9:5: error: ‘cin’ was not declared in this scope
     cin>>a>>b>>x>>y;
     ^~~
Main.cc:9:5: note: suggested alternative: ‘sin’
     cin>>a>>b>>x>>y;
     ^~~
     sin
Main.cc:9:16: error: ‘x’ was not declared in this scope
     cin>>a>>b>>x>>y;
                ^
Main.cc:10:5: error: ‘cout’ was not declared in this scope
     cout<<(a*x)+(b*y);
     ^~~~
Main.cc:10:5: note: suggested alternative: ‘cosl’
     cout<<(a*x)+(b*y);
     ^~~~
     cosl
Main.cc:8:15: warning: unused variable ‘X’ [-Wunused-variable]
     int a, b, X, y;
               ^