希尔排序

http://baike.baidu.com/view/1110250.htm
pascal的

program shell;
const n=7;
type
arr=array[1..n] of integer;
var
a:arr;
i,j,t,d:integer;
bool:boolean;
begin
write('input data:');
for i:=1 to n do read(a[i]);
writeln;
d:=n;
while d>1 do
begin
d:=d div 2;
for j:=d+1 to n do
begin
t:=a[j];i:=j-d;
while (i>0) and (a[i]>t) do
begin a[i+d]:=a[i];i:=i-d;end;
a[i+d]:=t;
end;
end;
write('output data:');
for i:=1 to n do write(a[i]:6);
writeln;
end.xepx