/in/foo.cc: In function 'int change1(int, int)':
/in/foo.cc:21:10: warning: statement has no effect [-Wunused-value]
  for ( kk;kk ;kk/=10 )
          ^
/in/foo.cc:23:29: error: 'pow' was not declared in this scope
   k1 += (kk % 10) * pow(p, i);
                             ^