/in/foo.cc: In function 'int main()':
/in/foo.cc:27:53: warning: 'key' may be used uninitialized in this function [-Wmaybe-uninitialized]
   else if(a[i]>='A'&&a[i]<='Z') cout<<b[(a[i]-'A'+27+key)%26+27];
                                         ~~~~~~~~~~~~^~~~~