高精度。
有一个贪心的公式。
程序如下：
program Ural_1108(Input,Output);
const
MaxLen=30000;
BitValue=100000000;
BitWidth=8;
MaxBitLen=MaxLen div BitWidth;
type
TIndex=Longint;
THP=record
Len:TIndex;
D:array[1..MaxBitLen]of Int64;
end;
var
N:TIndex;
F:THP;
function SqrHPPro(F:THP):THP; //n*(n-1)+1
var
i,j:TIndex;
begin
//note: 累加的时候 要与 进位分开0.3s 否则 1.4s
FillChar(Result,SizeOf(Result),0);
for i:=1 to F.Len do
for j:=1 to F.Len do
if i=1 then Inc(Result.D[i+j-1],(F.D-1)*F.D[j])
else Inc(Result.D[i+j-1],F.D*F.D[j]);
Result.Len:=F.Len*2;
Inc(Result.D[1]);
for i:=1 to Result.Len-1 do
begin
Inc(Result.D[i+1],Result.D div BitValue);
Result.D:=Result.D mod BitValue;
end;
while (Result.D[Result.Len]=0) and (Result.Len>1) do Dec(Result.Len);
end;
procedure Print;
var
i,j:TIndex;
St:String;
begin
for i:=F.Len downto 1 do
begin
if i<F.Len then
begin
Str(F.D:BitWidth,St);
for j:=1 to BitWidth do //replace ' ' with '0'
if St[j]=' ' then St[j]:='0';
end
else Str(F.D,St);
Write(St);
end;
Writeln;
end;
procedure Main;
var
i:TIndex;
begin
Readln(N);
F.Len:=1;
F.D[1]:=2;
Print;
for i:=2 to N do
begin
F:=SqrHPPro(F);
Print;
end;
end;
begin
Main;
end.
