/in/foo.cc: In function 'int main()':
/in/foo.cc:7:12: error: 'a' was not declared in this scope
       cin>>a[i];
            ^
/in/foo.cc:13:13: error: 'a' was not declared in this scope
       cout<<a[i]<<" ";
             ^
/in/foo.cc:16:13: error: 'a' was not declared in this scope
       cout<<a[i]<<" ";
             ^
/in/foo.cc:19:13: error: 'a' was not declared in this scope
       cout<<a[n+1]<<endl;
             ^