free pascal 改程序

实在看不懂
判断质数的地方应该是对的,可是判断回文的地方太复杂了
最好用两个函数来做:
function zhishu(x:integer):boolean;
太麻烦了,略过~~~~~
function huiwen(x:integer):boolean;
var s:string;
i,j:integer;
begin
s:=str(x);
i:=0;
j:=length(s)+1;
huiwen:=true;
repeat
inc(i);
dec(j);
if s[i]s[j] then begin
huiwen:=false;
break;
end;
until i>=j;
end;
var a,b,i:longint;
begin
while not eof do
begin
readln(a,b);
for i:=a to b do
begin
if zhishu(i) and huiwen(i) then writeln(i);
end;
end;
end.
好久没碰这个了,可能有点语法错误,自个儿看着改吧