exBSGS模板

题目bzoj2480，bzoj1467，贴个板子上来吧

program j01;
const mo=1000007;
var head:array[0..mo]of int64;
    hash,next,data:array[0..mo]of int64;
    a,b,p,tt:int64;
 
function gcd(a,b:int64):int64;
begin
  if b=0 then exit(a) else exit(gcd(b,a mod b));
end;
 
function pow(a,i,mm:int64):int64;
var y:int64;
begin
  if i=0 then exit(1);
  y:=pow(a,i div 2,mm) mod mm;
  y:=y*y mod mm;
  if i mod 2=1 then y:=y*a mod mm;
  exit(y);
end;
  
procedure push(i,w:int64);
var x:int64;
begin
  x:=i mod mo;
  inc(tt);
  hash[tt]:=i;data[tt]:=w;
  next[tt]:=head[x];
  head[x]:=tt;
end;
 
function find(i:int64):int64;
var j:int64;
begin
  j:=head[i mod mo];
  while j>0 do
  begin
    if hash[j]=i then exit(data[j]);
    j:=next[j];
  end;
  exit(-1);
end;
  
procedure solve;
var i:longint;
    n,now,tmp,x,m,d,cnt,t:int64;
begin
  a:=a mod p;b:=b mod p;
  if b=1 then
  begin
    writeln(0);exit;
  end;
  cnt:=0;t:=1;
  while true do
  begin
    d:=gcd(a,p);
    if d=1 then break;
    if b=t then
    begin
      writeln(cnt);exit;
    end;
    if not(b mod d=0) then
    begin
       writeln('No Solution');exit;
    end;
    p:=p div d;b:=b div d;t:=(t*a div d)mod p;
    inc(cnt);
  end;
  tt:=0;fillchar(head,sizeof(head),0);
  m:=trunc(sqrt(p))+1;b:=b mod p;
  now:=b;push(now,0);
  for i:=1 to m do
  begin
    now:=now*a mod p;
    push(now,i);
  end;
  tmp:=pow(a,m,p);
  now:=t;
  for i:=1 to m do
  begin
    now:=now*tmp mod p;
    x:=find(now);
    if x>-1 then
    begin
      writeln(i*m-x+cnt);
      exit;
    end;
  end;
  writeln('No Solution');
end;
 
begin
  while true do
  begin
    readln(a,p,b);
    if (a=0)and(b=0)and(p=0) then break;
    solve;
  end;
end.