Недавно написал под Делфи жду советов по оптимизации сего (выкидываю весь юнит):
| Код |
unit StrNumber;
interface
const
CHAR_TO_INT:array['0'..'9'] of Byte = (0,1,2,3,4,5,6,7,8,9);
INT_TO_CHAR:array[0..9] of Char = ('0','1','2','3','4','5','6','7','8','9');
function STR_ADD(S1,S2:AnsiString):AnsiString;
function STR_MUL_CHAR(S:AnsiString;C:Char):AnsiString;
function STR_MUL(S1,S2:AnsiString):AnsiString;
function STR_SUB(S1,S2:AnsiString):AnsiString;
function STR_MOD(S1,S2:AnsiString):AnsiString;
implementation
function CheckBuf(B:AnsiString):boolean;
var
j:integer;
begin
j:=1;
Result:=false;
while j<=Length(B) do
begin
if B[j]='1' then
begin
Result:=true;
j:=Length(B)+1;
end;
inc(j);
end;
end;
function STR_ADD(S1,S2:AnsiString):AnsiString;
var
i:integer;
Buf,
S3:AnsiString;
C1,
C2,
C3:Byte;
begin
Buf:='0';
if Length(S2)>Length(S1) then
begin
Result:=STR_ADD(S2,S1);
end
else
begin
for i:=1 to Length(S1)-Length(S2) do
begin
S2:='0'+S2;
end;
for i:=Length(S2) downto 1 do
begin
C1:=CHAR_TO_INT[S1[i]];
C2:=CHAR_TO_INT[S2[i]];
C3:=C1+C2;
if C3>=10 then
begin
Buf:='1'+Buf;
C3:=C3-10;
end
else
begin
if i<>1 then
begin
Buf:='0'+Buf;
end;
end;
S3:=INT_TO_CHAR[C3]+S3;
end;
if CheckBuf(Buf) then
begin
Result:=STR_ADD(Buf,S3);
end
else
begin
Result:=S3;
end;
end;
end;
function STR_MUL_CHAR(S:AnsiString;C:Char):AnsiString;
var
i:integer;
S3,
Buf:AnsiString;
C1,
C2,
C3:Byte;
begin
C1:=CHAR_TO_INT[C];
Buf:='0';
S3:='';
for i:=Length(S) downto 1 do
begin
C2:=CHAR_TO_INT[S[i]];
C3:=C2*C1;
Buf:=INT_TO_CHAR[(C3 div 10)]+Buf;
S3:=INT_TO_CHAR[(C3 mod 10)]+S3;
end;
Result:=STR_ADD(Buf,S3);
end;
function STR_MUL(S1,S2:AnsiString):AnsiString;
var
Buf,
S3:AnsiString;
i,
j:integer;
begin
S3:='0';
Buf:='0';
if Length(S2)>Length(S1) then
begin
Result:=STR_MUL(S2,S1);
end
else
begin
for i:=Length(S2) downto 1 do
begin
Buf:=STR_MUL_CHAR(S1,S2[i]);
for j:=1 to Length(S2)-i do
begin
Buf:=Buf+'0';
end;
S3:=STR_ADD(Buf,S3);
end;
while S3[1]='0' do
begin
Delete(S3,1,1);
end;
if S3='' then S3:='0';
Result:=S3;
end;
end;
function STR_CMP(S1,S2:AnsiString):boolean;
var
i:integer;
begin
Result:=false;
if Length(S1)>Length(S2) then
begin
Result:=true;
end;
if Length(S2)>Length(S1) then
begin
Result:=false;
end;
if Length(S2)=Length(S1) then
begin
i:=1;
Result:=true;
while i<=Length(S1) do
begin
if CHAR_TO_INT[S2[i]]>CHAR_TO_INT[S1[i]] then
begin
i:=Length(S1);
Result:=false;
end
else
begin
if CHAR_TO_INT[S2[i]]<>CHAR_TO_INT[S1[i]] then
begin
i:=Length(S1);
Result:=true;
end;
end;
inc(i);
end;
end;
end;
function STR_SUB(S1,S2:AnsiString):AnsiString;
var
i:integer;
Buf,
S3:AnsiString;
begin
Buf:='0';
if not STR_CMP(S1,S2) then
begin
Result:='0';
end
else
begin
for i:=1 to Length(S1)-Length(S2) do
begin
S2:='0'+S2;
end;
for i:=Length(S1) downto 1 do
begin
if CHAR_TO_INT[S1[i]]<CHAR_TO_INT[S2[i]] then
begin
Buf:='1'+Buf;
S3:=INT_TO_CHAR[CHAR_TO_INT[S1[i]]-CHAR_TO_INT[S2[i]]+10]+S3;
end
else
begin
Buf:='0'+Buf;
S3:=INT_TO_CHAR[CHAR_TO_INT[S1[i]]-CHAR_TO_INT[S2[i]]]+S3;
end;
end;
if CheckBuf(Buf) then
begin
while Buf[1]='0' do
begin
Delete(Buf,1,1);
end;
Result:=STR_SUB(S3,Buf);
end
else
begin
Result:=S3;
end;
end;
end;
function STR_MOD(S1,S2:AnsiString):AnsiString;
var
S3,
Z,
Mul:AnsiString;
i:integer;
begin
if not STR_CMP(S1,S2) then
begin
Result:=S1;
end
else
begin
Z:='';
for i:=1 to Length(S1)-Length(S2) do
begin
Z:=Z+'0';
end;
while Z<>'' do
begin
i:=1;
while i<10 do
begin
if not STR_CMP(S1,STR_MUL(S2,INT_TO_CHAR[i]+Z)) then
begin
dec(i);
if i>0 then
begin
S1:=STR_SUB(S1,STR_MUL(S2,INT_TO_CHAR[i]+Z));
end;
Delete(Z,1,1);
i:=11;
while S1[1]='0' do
begin
Delete(S1,1,1);
end;
if S1='' then S1:='0';
end;
if i=9 then
begin
S1:=STR_SUB(S1,STR_MUL(S2,INT_TO_CHAR[i]+Z));
Delete(Z,1,1);
while S1[1]='0' do
begin
Delete(S1,1,1);
end;
if S1='' then S1:='0';
end;
inc(i);
end;
end;
While STR_CMP(S1,S2) do
begin
S1:=STR_SUB(S1,S2);
while S1[1]='0' do
begin
Delete(S1,1,1);
end;
if S1='' then S1:='0';
end;
Result:=S1;
end;
end;
end.
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Нужая ф-я function STR_MOD(S1,S2:AnsiString):AnsiString; |