/in/foo.cc: In function 'int fz(int, int, int)':
/in/foo.cc:8:7: warning: suggest parentheses around '+' inside '>>' [-Wparentheses]
  mid=l+r>>1;
      ~^~
/in/foo.cc:26:13: error: 'b' was not declared in this scope
   if(a[mid]>b)
             ^
/in/foo.cc:28:4: error: 'y' was not declared in this scope
    y=mid-1;
    ^
/in/foo.cc:30:13: error: 'b' was not declared in this scope
   if(a[mid]<b)
             ^
/in/foo.cc:37:1: warning: control reaches end of non-void function [-Wreturn-type]
 }
 ^