/in/foo.cc: In function 'long long int insert(long long int)':
/in/foo.cc:156:1: warning: no return statement in function returning non-void [-Wreturn-type]
 }
 ^
/in/foo.cc: In function 'long long int del(long long int)':
/in/foo.cc:160:9: warning: unused variable 'k' [-Wunused-variable]
     int k=rank1(xx,rt);
         ^
/in/foo.cc:169:1: warning: no return statement in function returning non-void [-Wreturn-type]
 }
 ^