/in/foo.cc: In function 'int main()':
/in/foo.cc:6:6: warning: unused variable 'tian' [-Wunused-variable]
  int tian,d,n,x,y,l=0,sum=0,m1=0,m2=0,n1=1;
      ^~~~
/in/foo.cc:6:29: warning: unused variable 'm1' [-Wunused-variable]
  int tian,d,n,x,y,l=0,sum=0,m1=0,m2=0,n1=1;
                             ^~
/in/foo.cc:6:34: warning: unused variable 'm2' [-Wunused-variable]
  int tian,d,n,x,y,l=0,sum=0,m1=0,m2=0,n1=1;
                                  ^~