/in/foo.cc: In function 'int ri(int, int)':
/in/foo.cc:43:7: warning: variable 'flag' set but not used [-Wunused-but-set-variable]
  bool flag=false;
       ^~~~
/in/foo.cc: In function 'bool check(int)':
/in/foo.cc:87:3: warning: 'j' may be used uninitialized in this function [-Wmaybe-uninitialized]
   if(j==i)
   ^~