/in/foo.cc: In function 'void Build_tree(int, int, int)':
/in/foo.cc:33:11: warning: suggest parentheses around '+' inside '>>' [-Wparentheses]
  int mid=l+r>>1;
          ~^~
/in/foo.cc: In function 'void add(int, int, int, double, double)':
/in/foo.cc:74:18: warning: suggest parentheses around '+' inside '>>' [-Wparentheses]
  int mid=T[now].l+T[now].r>>1;
          ~~~~~~~~^~~~~~~~~
/in/foo.cc: In function 'void mul(int, int, int, double, double)':
/in/foo.cc:85:18: warning: suggest parentheses around '+' inside '>>' [-Wparentheses]
  int mid=T[now].l+T[now].r>>1;
          ~~~~~~~~^~~~~~~~~
/in/foo.cc: In function 'void find(int, int, int)':
/in/foo.cc:100:18: warning: suggest parentheses around '+' inside '>>' [-Wparentheses]
  int mid=T[now].l+T[now].r>>1;
          ~~~~~~~~^~~~~~~~~