function nodiv(s:string):string ;
var
i,L,le,ri:integer;
j,k:double ;
begin
s:=nospace(s);
result:=s;
L:=length(s);
i:=firstsignex(s,\'/\');
if (i=0) or (s[i]<>\'/\') then exit;
le:=leftsigh(s,i);
j:=leftnum(s,i);
k:=rightnum(s,i);
ri:=rightsigh(s,i);
if j/k>=0 then
result:=nodiv(leftstr(s,le-1)+floattostr(j/k)+rightstr(s,L-ri))
else
result:=nodiv(leftstr(s,le-1)+\'(\'+floattostr(j/k)+\')\'+rightstr(s,L-ri))
end;
function noadd(s:string):string ;
var
i,L,le,ri:integer;
j,k:double ;
begin
s:=nospace(s);
result:=s;
L:=length(s);
i:=firstsignex(s,\'+\');
if (i=0) or (s[i]<>\'+\') then exit;
le:=leftsigh(s,i);
j:=leftnum(s,i);
k:=rightnum(s,i);
ri:=rightsigh(s,i);
if j+k>=0 then
result:=noadd(leftstr(s,le-1)+floattostr(j+k)+rightstr(s,L-ri))
else
result:=noadd(leftstr(s,le-1)+\'(\'+floattostr(j+k)+\')\'+rightstr(s,L-ri))
end;
function nosub(s:string):string ;
var
i,L,le,ri:integer;
j,k:double ;
begin
s:=nospace(s);
result:=s;
L:=length(s);
i:=firstMinussignEX(s);
if (i=0) or (s[i]<>\'-\') then exit;
le:=leftsigh(s,i);
j:=leftnum(s,i);
k:=rightnum(s,i);
ri:=rightsigh(s,i);
if j-k>=0 then
result:=nosub(leftstr(s,le-1)+floattostr(j-k)+rightstr(s,L-ri))
else
result:=nosub(leftstr(s,le-1)+\'(\'+floattostr(j-k)+\')\'+rightstr(s,L-ri))
end;
function alltoone(s:string):string ;
begin
s:=nomulti(s);
s:=nodiv(s);
s:=noadd(s);
s:=nosub(s);
result:=s;
end;
function myexpress(s:string):string;
var
c,j,L:integer;
le,ri,al,substr,s0:string;
tryit:double;
begin
s:=nospace(s);
s0:=s;
L:=length(s);
if (s[1]<>\'(\') or (s[L]<>\')\') then
s:=\'(\'+s+\')\';
if (s[1]=\'(\') and (s[L]=\')\') and((s[2]=\'-\') or (isminus(s,L))) then
s:=\'(\'+s+\')\';
L:=length(s);
j:=firstJ(s);
c:=firstc(s,j);
if (j<L) and (c>1) and (j>c) then
begin
substr:=copy(s,c+1,j-c-1);
file://le:=leftstr(s,c-1);
file://ri:= rightstr(s,L-j);
le:=leftstr(s,c-1);
le:=rightstr(le,length(le)-1);
ri:= rightstr(s,L-j);
ri:=leftstr(ri,length(ri)-1);
file://showmessage(substr);
al:=alltoone(substr);
file://showmessage(le+al+ri);
result:=myexpress(le+al+ri);
end
else
result:=alltoone(s0);
end;
procedure TForm1.Button1Click(Sender: TObject);
begin
Edit2.Text:=myexpress(edit1.text);
end;
end.
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