Run id: 126204

Main.cc: In function 'int main()':
Main.cc:6:4: error: 'cin' was not declared in this scope
    cin>>a; 
    ^
Main.cc:8:4: error: 'cout' was not declared in this scope
    cout<<(c+10-30)*20/5; 
    ^
Main.cc:4:11: warning: unused variable 'b' [-Wunused-variable]
    char a,b; 
           ^