/in/foo.cc: In function 'int eshai(int)':
/in/foo.cc:36:1: warning: no return statement in function returning non-void [-Wreturn-type]
 }
 ^
/in/foo.cc: In function 'int get_n_prime(int, int*)':
/in/foo.cc:42:22: warning: comparison between signed and unsigned integer expressions [-Wsign-compare]
     for(int i = 0; i < prime.size() && prime[i] <= n; i++){
                    ~~^~~~~~~~~~~~~~
/in/foo.cc:52:1: warning: no return statement in function returning non-void [-Wreturn-type]
 }
 ^