Problem
素数是的只能被1和它本身整除的自然数。

Input
本题有多组数据，每组数据由两个正整数M,N组成。（0＜M＜N＜1000000）

Output
输出一个整数，表示介于M,N之间（包括M,N）的素数的数量。

Sample Input
5 10
1 3
6 8

Sample Output
2
1
1

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program lx1010;
var i,m,n,x,y,k:integer;
procedure s1(var a:integer);
begin
  if a<=k then x:=x+1
  else
    begin
      k:=k*10;
      s1(a);
    end;
end;
procedure s2(var b:integer);
begin
  if b<=k then y:=y+1
  else
    begin
      k:=k*10;
      s2(b);
    end;
end;
procedure ss;
var q,p:integer;
begin
  read(m,n);
  s1(m);
  k:=10;
  s2(n);
  k:=10;
  q:=trunc(m/(2.3*x));
  p:=trunc(n/(2.3*y));
  writeln(p-q);
  x:=0;
  y:=0;
  ss;
end;
begin
  k:=10;
  x:=0;
  y:=0;
  ss;
end.
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好象算出来是对的啊~~就是电脑通不过啊~~郁闷啊