function binsearch(k:keytype):integer; |
var low,hig,mid:integer; |
begin |
low:=1;hig:=n; |
mid:=(low+hig) div 2; |
while (a[mid].key<>k) and (low<=hig) do begin |
if a[mid].key>k then hig:=mid-1 |
else low:=mid+1; |
mid:=(low+hig) div 2; |
end; |
if low>hig then mid:=0; |
binsearch:=mid; |
end; |