记录编号	7515	评测结果	AAAAAAAAAA
题目名称	[BYVoid S1] 血色叛徒	最终得分	100
用户昵称	苏轼	是否通过	通过
代码语言	Pascal	运行时间	0.534 s
提交时间	2008-11-10 16:36:16	内存使用	2.50 MiB

program cch(input,output);
const
 xx:array[1..4] of integer=(-1,0,1,0);
 yy:array[1..4] of integer=(0,1,0,-1);
type
 sz=record
     x:integer;
     y:integer;
     k:integer;
    end;
var
 x,y,i,j,s,c,n,m,x1,y1,head,tail,k:longint;
 a:array[1..250000] of sz;
 f:array[1..500,1..500] of longint;

begin
 assign(input,'crusade.in');
 assign(output,'crusade.out');
 reset(input);
 rewrite(output);
 readln(n,m,s,c);
 for i:=1 to n do
  for j:=1 to m do f[i,j]:=-1;
 for i:=1 to s do
  begin
   readln(x,y);
   a[i].x:=x; a[i].y:=y; a[i].k:=0;
   f[x,y]:=0;
  end;
 head:=1; tail:=s;
 repeat
  for i:=1 to 4 do
   begin
    x1:=a[head].x+xx[i];
    y1:=a[head].y+yy[i];
    k:=a[head].k+1;
    if (x1>=1)and(x1<=n)and(y1>=1)and(y1<=n) then
     if f[x1,y1]=-1 then
      begin
       inc(tail);
       a[tail].x:=x1; a[tail].y:=y1;
       a[tail].k:=k;
       f[x1,y1]:=k;
      end;
   end;
  inc(head);
 until head>tail;
 for i:=1 to c do
  begin
   readln(x1,y1);
   writeln(f[x1,y1]);
  end;
 close(input);
 close(output);
end.