Program Interfase;
Uses crt;
Type win=Record
     x1,y1,x2,y2:word;
     text:string[15];
     end;
     sets=set of byte;
Const Menu:array[1..5]of win=((x1:1;y1:1;x2:16;y2:1;text:'Invertation'),
                              (x1:1;y1:2;x2:16;y2:2;text:'Summ'),
                              (x1:1;y1:3;x2:16;y2:3;text:'Difference'),
                              (x1:1;y1:4;x2:16;y2:4;text:'Multiplication'),
                              (x1:1;y1:5;x2:16;y2:5;text:'Division'));
      ns:sets=[1,2];
      answers:sets=[1..5];

Var a1,b1,a2,b2,a,b:integer;
    c1,c2,c:real;
    st1,st2,st,sa1,sb1,sa2,sb2,sa,sb:string;
    n,n1,k,i,err,err1,err2:integer;
    Npos:integer;
    answer:integer;
    ch1,ch2:char;
    Protokol:text;

{ЏаЁЈ« 襭ЁҐ}
Procedure Invitation(x1,y1,x2,y2:word;text:string[70]);
Begin
  Window(x1,y1,x2,y2);
  TextAttr:=15*16;
  Clrscr;
  GotoXY(x1,y1);
  Write(text);
End;

{Џа®ўҐаЄ  ўлЎ®а  ¤а®ЎЁ Ё ®вўҐв }
Procedure CheckUp(var variable:integer;checkset:sets);
Begin
  While not (variable in checkset) do
    Begin
      Invitation(1,7,80,8,'Error! You input incorrect meaning. Write over: ');
      Readln(variable);
    End;
End;

{‚лў®¤ §­ Є  ®ЇҐа жЁЁ}
Procedure Operation(x1,y1,x2,y2:word;sign:char);
Begin
  Window(x1,y1,x2,y2);
  TextAttr:=15*16;
  Clrscr;
  GotoXY(x1,y1);
  Write(sign);
End;

{ђЁб®ў ­ЁҐ Їг­Єв  ¬Ґ­о}
Procedure DrawWin(w:win;attr:byte);
Begin
  With w do
    Begin
      Textattr:=attr;
      Window(x1,y1,x2,y2);
      Clrscr;
      GotoXY(1,1);
      Write(text);
    End;
End;

{ђЁб®ў ­ЁҐ ¬Ґ­о б ўл¤Ґ«Ґ­­л¬ Їг­Єв®¬}
Procedure DrawMenu(Npos:integer);
Begin
  Clrscr;
  For i:=1 to 5 do
    If i=Npos Then DrawWin(menu[i],94)
    Else DrawWin(menu[i],30);
End;

{‚ў®¤ ®ЎлЄ­®ўҐ­­®© ¤а®ЎЁ}
Procedure InputCommonFraction(var nums,dens:string;var num,den:integer;err1,err2:integer;x1,y1,x2,y2:word);
Begin
  Repeat
    Window(x1,y1,x2,y2);
    TextAttr:=15*16;
    Clrscr;
    GotoXY(x1,y1);
    Readln(nums);
    Val(nums,num,err1);
    Window(x1,y1+1,x2,y2+1);
    TextAttr:=15*16;
    Clrscr;
    GotoXY(x1,y1+1);
    Write('____');
    Window(x1,y1+2,x2,y2+2);
    TextAttr:=15*16;
    Clrscr;
    GotoXY(x1,y1+2);
    Readln(dens);
    Val(dens,den,err2);
    If (err1<>0) Or (err2<>0) Or ((err1<>0) And (err2<>0)) Or (den=0) Then
      Invitation(1,7,80,8,'Error! You input incorrect meaning. Write over: ');
  Until (err1=0) And (err2=0) And (den<>0);
End;

{‚ў®¤ ¤ҐбпвЁз­®© ¤а®ЎЁ}
Procedure InputDecimalFraction(var decfr:string;var fr:real;err:integer;x1,y1,x2,y2:word);
Begin
  Repeat
    Window(x1,y1,x2,y2);
    TextAttr:=15*16;
    Clrscr;
    GotoXY(x1,y1);
    Readln(decfr);
    Val(decfr,fr,err);
    If err<>0 Then Invitation(1,7,80,8,'Error! You input incorrect meaning. Write over: ');
  Until err=0;
End;

{‚лў®¤ ®ЎлЄ­®ўҐ­­®© ¤а®ЎЁ}
Procedure OutPutCommonFraction(var num,den:integer;x1,y1,x2,y2:word);
Begin
  Window(x1,y1,x2,y2);
  TextAttr:=15*16;
  Clrscr;
  GotoXY(x1,y1);
  Write(num);
  Window(x1,y1+1,x2,y2+1);
  TextAttr:=15*16;
  Clrscr;
  GotoXY(x1,y1+1);
  Write('____');
  Window(x1,y1+2,x2,y2+2);
  TextAttr:=15*16;
  GotoXY(x1,y1+2);
  Write(den);
End;

{‚лў®¤ ¤ҐбпвЁз­®© ¤а®ЎЁ}
Procedure OutputDecimalFraction(var fr:real;x1,y1,x2,y2:word);
Begin
  Window(x1,y1,x2,y2);
  TextAttr:=15*16;
  Clrscr;
  GotoXY(x1,y1);
  Write(fr:3:3);
End;

{‘㬬  ®ЎлЄ­®ўҐ­­ле ¤а®ЎҐ©}
Procedure SummCommonFractions(var num1,den1,num2,den2,num,den:integer);
Begin
  If den1<>den2 Then
    Begin
      num:=num1*den2+num2*den1;
      den:=den1*den2;
    End
  Else
    Begin
      num:=num1+num2;
      den:=den1;
    End;
End;

{‘㬬  ¤ҐбпвЁз­ле ¤а®ЎҐ©}
Procedure SummDecimalFractions(var fr1,fr2,fr:real);
Begin
  fr:=fr1+fr2;
End;

{ЏҐаҐў®¤ ¤ҐбпвЁз­®© ¤а®ЎЁ ў ®ЎлЄ­®ўҐ­­го}
Procedure InvertDecFrIntoCommon(var decfr:string;var fr:real;var num,den:integer);
Var i,k:integer;
    power:real;
Begin
  For i:=length(decfr) downto 1 do
    If decfr[length(decfr)]='0' Then
      Delete(decfr,length(decfr),1);
  For i:=length(decfr) downto 1 do
    If decfr[i]='.' Then k:=i;
  If frac(fr)=0 Then power:=0
  Else power:=length(decfr)-k;
  den:=trunc(exp(power)*ln(10));
  num:=round(fr*den);
End;

{ЏҐаҐў®¤ ®ЎлЄ­®ўҐ­­®© ¤а®ЎЁ ў ¤ҐбпвЁз­го}
Procedure InvertComFrIntoDecimal(var num,den:integer;var fr:real);
Begin
  fr:=num/den;
End;

{ђ §­®бвм ®ЎлЄ­®ўҐ­­ле ¤а®ЎҐ©}
Procedure DifferenceCommonFractions(var num1,den1,num2,den2,num,den:integer);
Begin
  If den1<>den2 Then
    Begin
      num:=num1*den2-num2*den1;
      den:=den1*den2;
    End
  Else
    Begin
      num:=num1-num2;
      den:=den1;
    End;
End;

{ђ §­®бвм ¤ҐбпвЁз­ле ¤а®ЎҐ©}
Procedure DifferenceDecimalFractions(var fr1,fr2,fr:real);
Begin
  fr:=fr1-fr2;
End;

{”¬­®¦Ґ­ЁҐ ®ЎлЄ­®ўҐ­­ле ¤а®ЎҐ©}
Procedure MultiplicationCommonFractions(var num1,den1,num2,den2,num,den:integer);
Begin
  num:=num1*num2;
  den:=den1*den2;
End;

{”¬­®¦Ґ­ЁҐ ¤ҐбпвЁз­ле ¤а®ЎҐ©}
Procedure MultiplicationDecimalFractions(var fr1,fr2,fr:real);
Begin
  fr:=fr1*fr2;
End;

{„Ґ«Ґ­ЁҐ ®ЎлЄ­®ўҐ­­ле ¤а®ЎҐ©}
Procedure DivisionCommonFractions(var num1,den1,num2,den2,num,den:integer);
Begin
  num:=num1*den2;
  den:=den1*num2;
End;

{„Ґ«Ґ­ЁҐ ¤ҐбпвЁз­ле ¤а®ЎҐ©}
Procedure DivisionDecimalFractions(var fr1,fr2,fr:real);
Begin
  fr:=fr1/fr2;
End;

{‘®Єа 饭ЁҐ ®ЎлЄ­®ўҐ­­®© ¤а®ЎЁ}
Procedure CancellationCommonFraction(var num,den:integer);
Var nod,r,n1,n2:integer;
Begin
  n1:=abs(den);
  n2:=abs(num);
  While (n1 mod n2)<>0 do
    Begin
      r:=n1 mod n2;
      n1:=n2;
      n2:=r;
    End;
  nod:=n2;
  num:=trunc(num/nod);
  den:=trunc(den/nod);
End;

{Ѓ«®Є ®б­®ў­®© Їа®Ја ¬¬л}
Begin
  Clrscr;
  Assign(Protokol,'C:/Temp/Betaversion.txt');
  ReWrite(Protokol);
  Window(1,1,80,30);
  TextAttr:=7*16;
  Clrscr;
  Npos:=1;
  DrawMenu(Npos);
  Repeat
    Ch1:=ReadKey;
    If ch1=#0 Then ch2:=ReadKey;
    Case ch1 of
    #0: Case ch2 of
        #72: Begin
               If Npos>1 Then
                 Begin
                   DrawWin(menu[Npos],30);
                   Npos:=Npos-1;
                   DrawWin(menu[Npos],94);
                 End;
             End;
        #80: Begin
               If Npos<5 Then
                 Begin
                   DrawWin(menu[Npos],30);
                   Npos:=Npos+1;
                   DrawWin(menu[Npos],94);
                 End;
             End;
        End;
    #13: Begin
           Case Npos of
           1: Begin
                Invitation(1,7,80,8,'Input 1 if fraction is common and 2 if fraction is decimal: ');
                Readln(n);
                CheckUp(n,ns);
                Case n of
                1: Begin
                     If (a1<>0) and (b1<>0) Then OutputCommonFraction(a1,b1,2,10,6,11)
                     Else InputCommonFraction(sa1,sb1,a1,b1,err1,err2,2,10,6,11);
                     Operation(8,11,10,12,'=');
                     InvertComFrIntoDecimal(a1,b1,c);
                     OutputDecimalFraction(c,2,18,9,19);
                     Writeln(Protokol,a1,'____',b1,'=',c);
                   End;
                2: Begin
                     If c1<>0 Then OutputDecimalFraction(c1,2,11,9,12)
                     Else InputDecimalFraction(st1,c1,err,2,11,9,12);
                     Operation(11,11,12,12,'=');
                     InvertDecFrIntoCommon(st1,c1,a,b);
                     CancellationCommonFraction(a,b);
                     OutputCommonFraction(a,b,2,18,6,19);
                     Writeln(Protokol,c1,'=',a,'____',b);
                   End;
                End;
              End;
           2: Begin
                Invitation(1,7,80,8,'Input 1 if 1st fraction is common and 2 if 1st fraction is decimal: ');
                Readln(n);
                CheckUp(n,ns);
                Invitation(1,7,80,8,'Input 1 if 2nd fraction is common and 2 if 2nd fraction is decimal: ');
                Readln(n1);
                CheckUp(n1,ns);
                Case n of
                1: Begin
                     If (a1<>0) and (b1<>0) Then OutputCommonFraction(a1,b1,2,10,6,11)
                     Else InputCommonFraction(sa1,sb1,a1,b1,err1,err2,2,10,6,11);
                     Operation(7,11,9,12,'+');
                     Case n1 of
                     1: InputCommonFraction(sa2,sb2,a2,b2,err1,err2,10,10,14,11);
                     2: Begin
                          InputDecimalFraction(st2,c2,err,10,11,17,12);
                          InvertDecFrIntoCommon(st2,c2,a2,b2);
                        End;
                     End;
                     SummCommonFractions(a1,b1,a2,b2,a,b);
                     CancellationCommonFraction(a,b);
                     OutputCommonFraction(a,b,2,18,6,19);
                   End;
                2: Begin
                     If c1<>0 Then OutputDecimalFraction(c1,2,11,9,12)
                     Else InputDecimalFraction(st1,c1,err,2,11,9,12);
                     Operation(7,11,9,12,'+');
                     Case n1 of
                     1: Begin
                          InputCommonFraction(sa2,sb2,a2,b2,err1,err2,10,10,14,11);
                          InvertComFrIntoDecimal(a2,b2,c2);
                        End;
                     2: InputDecimalFraction(st2,c2,err,10,11,17,12);
                     End;
                     SummDecimalFractions(c1,c2,c);
                     OutputDecimalFraction(c,2,18,9,19);
                   End;
                End;
              End;
           3: Begin
                Invitation(1,7,80,8,'Input 1 if 1st fraction is common and 2 if 1st fraction is decimal: ');
                Readln(n);
                CheckUp(n,ns);
                Invitation(1,7,80,8,'Input 1 if 2nd fraction is common and 2 if 2nd fraction is decimal: ');
                Readln(n1);
                CheckUp(n1,ns);
                Case n of
                1: Begin
                     If (a1<>0) and (b1<>0) Then OutputCommonFraction(a1,b1,2,10,6,11)
                     Else InputCommonFraction(sa1,sb1,a1,b1,err1,err2,2,10,6,11);
                     Operation(7,11,9,12,'-');
                     Case n1 of
                     1: InputCommonFraction(sa2,sb2,a2,b2,err1,err2,10,10,14,11);
                     2: Begin
                          InputDecimalFraction(st2,c2,err,10,11,17,12);
                          InvertDecFrIntoCommon(st2,c2,a2,b2);
                        End;
                     End;
                     DifferenceCommonFractions(a1,b1,a2,b2,a,b);
                     CancellationCommonFraction(a,b);
                     OutputCommonFraction(a,b,2,18,6,19);
                   End;
                2: Begin
                     If c1<>0 Then OutputDecimalFraction(c1,2,11,9,12)
                     Else InputDecimalFraction(st1,c1,err,2,11,9,12);
                     Operation(7,11,9,12,'-');
                     Case n1 of
                     1: Begin
                          InputCommonFraction(sa2,sb2,a2,b2,err1,err2,10,10,14,11);
                          InvertComFrIntoDecimal(a2,b2,c2);
                        End;
                     2: InputDecimalFraction(st2,c2,err,10,11,17,12);
                     End;
                     DifferenceDecimalFractions(c1,c2,c);
                     OutputDecimalFraction(c,2,18,9,19);
                   End;
                End;
              End;
           4: Begin
                Invitation(1,7,80,8,'Input 1 if 1st fraction is common and 2 if 1st fraction is decimal: ');
                Readln(n);
                CheckUp(n,ns);
                Invitation(1,7,80,8,'Input 1 if 2nd fraction is common and 2 if 2nd fraction is decimal: ');
                Readln(n1);
                CheckUp(n1,ns);
                Case n of
                1: Begin
                     If (a1<>0) and (b1<>0) Then OutputCommonFraction(a1,b1,2,10,6,11)
                     Else InputCommonFraction(sa1,sb1,a1,b1,err1,err2,2,10,6,11);
                     Operation(7,11,9,12,'*');
                     Case n1 of
                     1: InputCommonFraction(sa2,sb2,a2,b2,err1,err2,10,10,14,11);
                     2: Begin
                          InputDecimalFraction(st2,c2,err,10,11,17,12);
                          InvertDecFrIntoCommon(st2,c2,a2,b2);
                        End;
                     End;
                     MultiplicationCommonFractions(a1,b1,a2,b2,a,b);
                     CancellationCommonFraction(a,b);
                     OutputCommonFraction(a,b,2,18,6,19);
                   End;
                2: Begin
                     If c1<>0 Then OutputDecimalFraction(c1,2,11,9,12)
                     Else InputDecimalFraction(st1,c1,err,2,11,9,12);
                     Operation(7,11,9,12,'*');
                     Case n1 of
                     1: Begin
                          InputCommonFraction(sa2,sb2,a2,b2,err1,err2,10,10,14,11);
                          InvertComFrIntoDecimal(a2,b2,c2);
                        End;
                     2: InputDecimalFraction(st2,c2,err,10,11,17,12);
                     End;
                     MultiplicationDecimalFractions(c1,c2,c);
                     OutputDecimalFraction(c,2,18,9,19);
                   End;
                End;
              End;
           5: Begin
                Invitation(1,7,80,8,'Input 1 if 1st fraction is common and 2 if 1st fraction is decimal: ');
                Readln(n);
                CheckUp(n,ns);
                Invitation(1,7,80,8,'Input 1 if 2nd fraction is common and 2 if 2nd fraction is decimal: ');
                Readln(n1);
                CheckUp(n1,ns);
                Case n of
                1: Begin
                     If (a1<>0) and (b1<>0) Then OutputCommonFraction(a1,b1,2,10,6,11)
                     Else InputCommonFraction(sa1,sb1,a1,b1,err1,err2,2,10,6,11);
                     Operation(7,11,9,12,'/');
                     Case n1 of
                     1: InputCommonFraction(sa2,sb2,a2,b2,err1,err2,10,10,14,11);
                     2: Begin
                          InputDecimalFraction(st2,c2,err,10,11,17,12);
                          InvertDecFrIntoCommon(st2,c2,a2,b2);
                        End;
                     End;
                     DivisionCommonFractions(a1,b1,a2,b2,a,b);
                     CancellationCommonFraction(a,b);
                     OutputCommonFraction(a,b,2,18,6,19);
                   End;
                2: Begin
                     If c1<>0 Then OutputDecimalFraction(c1,2,11,9,12)
                     Else InputDecimalFraction(st1,c1,err,2,11,9,12);
                     Operation(7,11,9,12,'/');
                     Case n1 of
                     1: Begin
                          InputCommonFraction(sa2,sb2,a2,b2,err1,err2,10,10,14,11);
                          InvertComFrIntoDecimal(a2,b2,c2);
                        End;
                     2: InputDecimalFraction(st2,c2,err,10,11,17,12);
                     End;
                     DivisionDecimalFractions(c1,c2,c);
                     OutputDecimalFraction(c,2,18,9,19);
                   End;
                End;
              End;
           End;
           Invitation(1,22,80,23,'Cancel(1)?/Continue(2)?/Begin at first(3)?/Open Protokol(4)?/Exit(5)? ');
           Readln(answer);
           CheckUp(answer,answers);
           If answer=1 Then
             Begin
               If (a<>0) And (b<>0) Then
                 Begin
                   a:=a1;
                   b:=b1;
                 End;
               If c<>0 Then
                 Begin
                   c:=c1;
                   str(c,st);
                 End;
               Window(1,7,80,25);
               TextAttr:=7*16;
               Clrscr;
             End;
           If answer=2 Then
             Begin
               If (a<>0) and (b<>0) Then
                 Begin
                   a1:=a;
                   b1:=b;
                 End;
               If c<>0 Then
                 Begin
                   c1:=c;
                   str(c1,st1);
                 End;
               Window(1,7,80,25);
               Textattr:=7*16;
               Clrscr;
             End;
           If answer=3 Then
             Begin
               Window(1,7,80,25);
               Textattr:=7*16;
               Clrscr;
               a1:=0;
               b1:=0;
               c1:=0;
             End;
           If answer=4 Then
             While not EOF(Protokol) do
               Begin
                 Readln(Protokol,a1,b1,c1,a,b,c);
                 Writeln(a1,b1,c1,a,b,c);
               End;
         End;
    End;
  Until answer=5;
  Close(Protokol);
End.