/in/foo.cc: In function 'int main()':
/in/foo.cc:19:14: warning: unused variable 'm' [-Wunused-variable]
  int n,k,x=0,m,i,s=0;
              ^
/in/foo.cc:19:16: warning: unused variable 'i' [-Wunused-variable]
  int n,k,x=0,m,i,s=0;
                ^