/in/foo.cc: In function 'int main()':
/in/foo.cc:4:6: warning: unused variable 's' [-Wunused-variable]
  int s,m;
      ^
/in/foo.cc:5:6: warning: unused variable 'a' [-Wunused-variable]
  int a[m];
      ^
/in/foo.cc:5:9: warning: 'm' is used uninitialized in this function [-Wuninitialized]
  int a[m];
         ^