/in/foo.cc: In function 'void Ins(int, int, int, int)':
/in/foo.cc:13:9: warning: suggest parentheses around '+' inside '>>' [-Wparentheses]
  int m=l+r>>1;
        ~^~
/in/foo.cc: In function 'int Ask(int, int, int, int, int)':
/in/foo.cc:75:9: warning: suggest parentheses around '+' inside '>>' [-Wparentheses]
  int m=l+r>>1;
        ~^~
/in/foo.cc: In function 'int lower(int)':
/in/foo.cc:84:12: warning: suggest parentheses around '+' inside '>>' [-Wparentheses]
   int mid=a+b>>1;
           ~^~
/in/foo.cc: In function 'int upper(int)':
/in/foo.cc:96:12: warning: suggest parentheses around '+' inside '>>' [-Wparentheses]
   int mid=a+b>>1;
           ~^~
/in/foo.cc: In function 'void DFS(int, int, int)':
/in/foo.cc:108:9: warning: suggest parentheses around '+' inside '>>' [-Wparentheses]
  int m=l+r>>1;
        ~^~