/in/foo.cc: In function 'int main()':
/in/foo.cc:6:10: warning: unused variable 'cnt' [-Wunused-variable]
  int L,R,cnt=0,sum=0,r,sum1=0;
          ^~~
/in/foo.cc:6:16: warning: unused variable 'sum' [-Wunused-variable]
  int L,R,cnt=0,sum=0,r,sum1=0;
                ^~~
/in/foo.cc:6:22: warning: unused variable 'r' [-Wunused-variable]
  int L,R,cnt=0,sum=0,r,sum1=0;
                      ^
/in/foo.cc:6:24: warning: unused variable 'sum1' [-Wunused-variable]
  int L,R,cnt=0,sum=0,r,sum1=0;
                        ^~~~
/in/foo.cc: In function 'int sw(int, int)':
/in/foo.cc:32:1: warning: no return statement in function returning non-void [-Wreturn-type]
 }
 ^