/in/foo.cc: In function 'int main()':
/in/foo.cc:4:15: warning: suggest parentheses around '+' inside '>>' [-Wparentheses]
 #define mid (l+r>>1)
              ~^~
/in/foo.cc:28:11: note: in expansion of macro 'mid'
   if (cnt(mid)>k) r=mid-1;
           ^~~
/in/foo.cc:4:15: warning: suggest parentheses around '+' inside '>>' [-Wparentheses]
 #define mid (l+r>>1)
              ~^~
/in/foo.cc:28:21: note: in expansion of macro 'mid'
   if (cnt(mid)>k) r=mid-1;
                     ^~~
/in/foo.cc:4:15: warning: suggest parentheses around '+' inside '>>' [-Wparentheses]
 #define mid (l+r>>1)
              ~^~
/in/foo.cc:29:10: note: in expansion of macro 'mid'
   else l=mid+1;
          ^~~