/in/foo.cc: In function 'void update(int&, int, int, int, int, int)':
/in/foo.cc:27:11: warning: suggest parentheses around '+' inside '>>' [-Wparentheses]
  int mid=l+r>>1;
          ~^~
/in/foo.cc: In function 'int query(int, int, int, int, int)':
/in/foo.cc:34:11: warning: suggest parentheses around '+' inside '>>' [-Wparentheses]
  int mid=l+r>>1,sum=sum(lson(t))-sum(lson(s));
          ~^~