Bzoj 1008 [hnoi2008]越狱prison

组合数学一下，快速幂..

之前写过了= =，只是忘记了（a-b）mod def = ((a mod def+def) –b)mod def

//bzoj 1008 hnoi2008prison
const
        def=100003;
var
        tmp, ans, m, n: qword;
function power(m, n: qword): qword;
var
        base: qword;
begin
  base := m;
  power := 1;
  while n<>0 do begin
    if n and 1 = 1 then power := power * base mod def;
    base := (base mod def)*(base mod def) mod def;
    n := n >> 1;
  end;
end;

procedure main;
begin
  readln(m, n);
  ans := power(m, n) mod def;
  tmp := m*power(m-1,n-1) mod def;
  ans := ((ans+def)-tmp)mod def;
  writeln(ans);
end;

begin
  main;
end.