/in/foo.cc: In function 'int find(int)':
/in/foo.cc:13:12: warning: suggest parentheses around '+' inside '>>' [-Wparentheses]
   int mid=l+r>>1;
           ~^~
/in/foo.cc:17:9: warning: 'pos' may be used uninitialized in this function [-Wmaybe-uninitialized]
  return pos;
         ^~~