/in/foo.cc: In function 'bool inc9(int)':
/in/foo.cc:7:7: warning: unused variable 'flag' [-Wunused-variable]
  bool flag=0;
       ^
/in/foo.cc: In function 'int main()':
/in/foo.cc:28:17: warning: 'k' may be used uninitialized in this function [-Wmaybe-uninitialized]
     for(int i=k+1;i<=n;i++){
                 ^