PROGRAM SIMPLEX(INPUT,OUTPUT);                              
(* ÈANNO ËLEIN 27.11.85 - 11.12.85*)                        
                                                            
CONST MAXZ=20;MAXSP=40;CLRSCR="“";CSRHOME="";              
      F1=133;F3=134;F5=135;F7=136;C=67;B=66;Q=81;           
      RON="";ROFF="’";CD="";CR="";CL="?";                
TYPE ZINDEX  = 1..MAXZ;                                     
     SPINDEX = 1..MAXSP;                                    
     CARDINAL= 0..MAXINT;                                   
     ZAHL    = RECORD                                       
                ZAEHLER : CARDINAL;                         
                NENNER  : CARDINAL;                         
                VORZ    : BOOLEAN                           
               END;                                         
     TABLEAU = ARRAY[ZINDEX,SPINDEX] OF ZAHL;               
     TKEY    = 0..255;                                      
VAR TAB         : TABLEAU;                                  
    KEY         : TKEY;                                     
    PIVOT       : ZAHL;                                     
    I,ANZZ,PZ   : ZINDEX;                                   
    J,ANZSP,PSP : SPINDEX;                                  
                                                            
PROCEDURE WAITKEY;                                          
 BEGIN                                                      
  WRITELN(CD,CR,CR,CR,CR,RON,"ÔASTE DRUECKEN");             
  REPEAT SYS(-28) UNTIL PEEK(780)<>0                        
 END; (*WAITKEY*)                                           
                                                            
PROCEDURE INIT;                                             
 BEGIN                                                      
  PZ:=0;PSP:=0;                                             
  REPEAT                                                    
   WRITELN(CLRSCR,"ÁNZAHL DER ÚEILEN     ");                
   WRITELN("==>",ANZZ);WRITELN(CSRHOME);                    
   WRITE(CR,CR,CR,CR);READLN(ANZZ);                         
   WRITELN(CD,CD,"ÁNZAHL DER ÓPALTEN    ");                 
   WRITELN("==>",ANZSP);WRITELN(CSRHOME);                   
   WRITE(CD,CD,CD,CD,CD,CR,CR,CR,CR);READLN(ANZSP)          
  UNTIL (ANZZ<=MAXZ) AND (ANZSP<=MAXSP)                     
 END; (*INIT*)                                              
                                                            
PROCEDURE CHECKFIELD(VAR FIELD:ZAHL;Z,N:INTEGER);           
 BEGIN                                                      
  IF N<0 THEN N:=-N;                                        
  IF (Z<0) AND (N<>0) THEN BEGIN Z:=-Z;FIELD.VORZ:=TRUE END 
     ELSE FIELD.VORZ:=FALSE;                                
  IF (Z=0) OR (N=0) THEN                                    
     BEGIN FIELD.ZAEHLER:=0;FIELD.NENNER:=0 END             
     ELSE                                                   
     BEGIN FIELD.ZAEHLER:=Z;FIELD.NENNER:=N END             
 END; (*CHECKFIELD*)                                        
                                                            
PROCEDURE PRINTFIELD(FIELD:ZAHL);                           
 VAR Z,N:CARDINAL;                                          
 BEGIN                                                      
  Z:=FIELD.ZAEHLER;N:=FIELD.NENNER;                         
  IF FIELD.VORZ THEN WRITE("-")                             
     ELSE IF Z<>0 THEN WRITE("+")                           
             ELSE WRITE(" ");WRITE(Z:3);                    
  IF (N<>1) AND (N<>0) THEN WRITELN(" /",N) ELSE WRITELN    
 END; (*PRINTFIELD*)                                        
                                                            
PROCEDURE EINGABE;                                          
 VAR I,K:ZINDEX;J:SPINDEX;Z,N:INTEGER;                      
 BEGIN                                                      
  FOR J:=1 TO ANZSP DO                                      
   BEGIN                                                    
    WRITELN(CLRSCR,RON,"ÓPALTE",J:3);                       
    FOR I:=1 TO ANZZ DO                                     
     BEGIN                                                  
      WRITELN(CSRHOME,CD);                                  
      FOR K:=1 TO I DO WRITE(CD);                           
      WRITE("ÚEILE",I:3," : 0 0",CL,CL,CL);READLN(Z,N);     
      CHECKFIELD(TAB[I,J],Z,N)                              
     END                                                    
   END                                                      
 END; (*EINGABE*)                                           
                                                            
PROCEDURE AUSGABE;                                          
 VAR I:ZINDEX;J:SPINDEX;                                    
 BEGIN                                                      
  FOR J:=1 TO ANZSP DO                                      
   BEGIN                                                    
    WRITELN(CLRSCR,RON,"ÓPALTE",J:3,CD);                    
    FOR I:=1 TO ANZZ DO                                     
     BEGIN                                                  
      WRITE("ÚEILE",I," : ");                               
      PRINTFIELD(TAB[I,J])                                  
     END;                                                   
    WAITKEY                                                 
   END                                                      
 END; (*AUSGABE*)                                           
                                                            
PROCEDURE KUERZE(VAR X,Y:CARDINAL);                         
 VAR GGT,XX,YY:CARDINAL;                                    
 BEGIN                                                      
  IF (X<>0) AND (Y<>0) THEN                                 
   BEGIN                                                    
    XX:=X;YY:=Y;                                            
    WHILE X<>Y DO                                           
     IF X>Y THEN X:=X-Y ELSE Y:=Y-X;                        
    GGT:=X;X:=XX DIV GGT;Y:=YY DIV GGT                      
   END                                                      
 END; (*KUERZE*)                                            
                                                            
PROCEDURE GETKGV(X,Y:CARDINAL;VAR KGV:CARDINAL);            
 VAR U,V:CARDINAL;                                          
 BEGIN                                                      
  IF (X=0) OR (Y=0) THEN KGV:=0                             
     ELSE BEGIN                                             
      U:=X;V:=Y;                                            
      WHILE X<>Y DO                                         
       IF X>Y THEN BEGIN X:=X-Y;U:=U+V END                  
          ELSE BEGIN Y:=Y-X;V:=V+U END;                     
      KGV:=(U+V) DIV 2                                      
     END                                                    
 END; (*GETKGV*)                                            
                                                            
PROCEDURE GETVORZEICHEN(V1,V2:BOOLEAN;VAR ERGV:BOOLEAN);    
 BEGIN                                                      
  IF (V1 AND V2) OR (NOT V1 AND NOT V2) THEN ERGV:=FALSE    
     ELSE ERGV:=TRUE                                        
 END; (*GETVORZEICHEN*)                                     
                                                            
PROCEDURE DIVIDE(Z1,Z2:ZAHL;VAR ERG:ZAHL);                  
 BEGIN                                                      
  IF (Z1.ZAEHLER<>0) AND (Z2.ZAEHLER<>0) THEN               
   BEGIN                                                    
    KUERZE(Z1.ZAEHLER,Z2.ZAEHLER);                          
    KUERZE(Z1.NENNER,Z2.NENNER);                            
    ERG.ZAEHLER:=Z1.ZAEHLER*Z2.NENNER;                      
    ERG.NENNER:=Z1.NENNER*Z2.ZAEHLER;                       
    KUERZE(ERG.ZAEHLER,ERG.NENNER);                         
    GETVORZEICHEN(Z1.VORZ,Z2.VORZ,ERG.VORZ)                 
   END                                                      
   ELSE IF Z2.ZAEHLER=0 THEN                                
         BEGIN                                              
          WRITELN(CLRSCR,"ÄIVISION BY ZERO !!!");WAITKEY    
         END                                                
   ELSE BEGIN                                               
         ERG.ZAEHLER:=0;ERG.NENNER:=0;ERG.VORZ:=FALSE       
        END                                                 
 END; (*DIVIDE*)                                            
                                                            
PROCEDURE MULTIPLY(Z1,Z2:ZAHL;VAR ERG:ZAHL);                
 BEGIN                                                      
  IF (Z1.ZAEHLER<>0) AND (Z2.ZAEHLER<>0) THEN               
   BEGIN                                                    
    KUERZE(Z1.ZAEHLER,Z2.NENNER);                           
    KUERZE(Z1.NENNER,Z2.ZAEHLER);                           
    ERG.ZAEHLER:=Z1.ZAEHLER*Z2.ZAEHLER;                     
    ERG.NENNER:=Z1.NENNER*Z2.NENNER;                        
    KUERZE(ERG.ZAEHLER,ERG.NENNER);                         
    GETVORZEICHEN(Z1.VORZ,Z2.VORZ,ERG.VORZ)                 
   END                                                      
   ELSE BEGIN                                               
         ERG.ZAEHLER:=0;ERG.NENNER:=0;ERG.VORZ:=FALSE       
        END                                                 
 END; (*MULTIPLY*)                                          
                                                            
PROCEDURE ADD(Z1,Z2:ZAHL;VAR ERG:ZAHL);                     
 VAR KGV:CARDINAL;SUMME,X1,X2:INTEGER;                      
 BEGIN                                                      
  GETKGV(Z1.NENNER,Z2.NENNER,KGV);                          
  IF KGV<>0 THEN                                            
   BEGIN                                                    
    ERG.NENNER:=KGV;                                        
    X1:=Z1.ZAEHLER*(KGV DIV Z1.NENNER);                     
    X2:=Z2.ZAEHLER*(KGV DIV Z2.NENNER);                     
    IF Z1.VORZ THEN X1:=-X1;IF Z2.VORZ THEN X2:=-X2;        
    SUMME:=X1+X2;                                           
    IF SUMME<0 THEN                                         
       BEGIN ERG.ZAEHLER:=-SUMME;ERG.VORZ:=TRUE END         
       ELSE BEGIN ERG.ZAEHLER:=SUMME;ERG.VORZ:=FALSE END    
   END                                                      
   ELSE BEGIN ERG.ZAEHLER:=Z1.ZAEHLER+Z2.ZAEHLER;           
    ERG.NENNER:=Z1.NENNER+Z2.NENNER;                        
    ERG.VORZ:=Z1.VORZ OR Z2.VORZ END;                       
   IF ERG.ZAEHLER=0 THEN ERG.NENNER:=0                      
    ELSE KUERZE(ERG.ZAEHLER,ERG.NENNER)                     
 END; (*ADD*)                                               
                                                            
PROCEDURE CHANGEFIELD;                                      
 VAR I:ZINDEX;J:SPINDEX;Z,N:INTEGER;                        
 BEGIN                                                      
  REPEAT                                                    
   WRITELN(CLRSCR,RON,"ÆELDAENDERUNG");                     
   WRITELN(CD,CD,"ÚEILE ÓPALTE");                           
   WRITE(CD,"==>");READLN(I,J);                             
  UNTIL (I>0) AND (I<=ANZZ) AND (J>0) AND (J<=ANZSP);       
  WRITELN(CD,CD,"ÚAEHLER ÎENNER");                          
  WRITE(CD,"==>");READLN(Z,N);CHECKFIELD(TAB[I,J],Z,N)      
 END; (*CHANGEFIELD*)                                       
                                                            
PROCEDURE CALCBRUCH;                                        
 VAR Z,N:REAL;                                              
 BEGIN                                                      
  REPEAT                                                    
   WRITELN(CLRSCR,RON,"ÂRUCH ==> ÄEZIMALWERT");             
   WRITELN(CD,CD,"ÚAEHLER ÎENNER");                         
   WRITE(CD,"==>");READLN(Z,N)                              
  UNTIL (INT(Z)=Z) AND (INT(N)=N);                          
  IF N=0 THEN WRITELN(CD,CD,"ÄIVISION BY ZERO !!!")         
     ELSE BEGIN                                             
      WRITELN(CD,CD,"ÄEZIMALWERT");                         
      WRITELN(CD,"==>",Z/N)                                 
     END;                                                   
  WAITKEY                                                   
 END; (*CALCBRUCH*)                                         
                                                            
PROCEDURE ITERATION;                                        
 VAR I:ZINDEX;J:SPINDEX;ERG,MP:ZAHL;Z,N:CARDINAL;           
                                                            
 PROCEDURE GETPIVOT;                                        
  BEGIN                                                     
   REPEAT                                                   
    WRITELN(CLRSCR,"ÐIVOT (ÚEILE ÓPALTE)  ");               
    WRITELN("==>",PZ,PSP);WRITELN(CSRHOME);                 
    WRITE(CR,CR,CR,CR);READLN(PZ,PSP)                       
   UNTIL (PZ<ANZZ)AND(PSP<ANZSP)AND(PZ>0)AND(PSP>0);        
   PIVOT:=TAB[PZ,PSP]                                       
  END; (*GETPIVOT*)                                         
                                                            
 BEGIN (*ITERATION*)                                        
  GETPIVOT;Z:=PIVOT.ZAEHLER;N:=PIVOT.NENNER;                
  IF Z<>0 THEN                                              
   BEGIN                                                    
    IF (Z<>1) OR (N<>1) THEN                                
     FOR J:=1 TO ANZSP DO IF TAB[PZ,J].ZAEHLER<>0 THEN      
      DIVIDE(TAB[PZ,J],PIVOT,TAB[PZ,J]);                    
    FOR I:=1 TO ANZZ DO                                     
     IF (I<>PZ) AND (TAB[I,PSP].ZAEHLER<>0) THEN            
      BEGIN MP:=TAB[I,PSP];                                 
       IF TAB[I,PSP].VORZ THEN MP.VORZ:=FALSE               
                          ELSE MP.VORZ:=TRUE;               
       FOR J:=1 TO ANZSP DO                                 
        IF TAB[PZ,J].ZAEHLER<>0 THEN                        
         BEGIN                                              
          MULTIPLY(MP,TAB[PZ,J],ERG);                       
          ADD(TAB[I,J],ERG,TAB[I,J])                        
         END                                                
      END                                                   
   END;AUSGABE                                              
 END; (*ITERATION*)                                         
                                                            
PROCEDURE QUOTIENT;                                         
 VAR I:ZINDEX;SP:SPINDEX;QUOT:ZAHL;                         
 BEGIN                                                      
  REPEAT                                                    
   WRITE(CLRSCR,RON,"ÓPALTE:",ROFF," ");READLN(SP)          
  UNTIL (SP>0) AND (SP<ANZSP);WRITELN;                      
  FOR I:=1 TO ANZZ-1 DO                                     
   BEGIN WRITE("ÚEILE",I:3," :");                           
    IF (TAB[I,SP].ZAEHLER=0) OR                             
       (TAB[I,SP].VORZ AND (TAB[I,ANZSP].ZAEHLER<>0)) THEN  
       WRITELN(" ./.")                                      
       ELSE BEGIN                                           
        DIVIDE(TAB[I,ANZSP],TAB[I,SP],QUOT);                
        IF TAB[I,SP].VORZ THEN WRITELN(" (EVTL.)")          
           ELSE PRINTFIELD(QUOT)                            
       END                                                  
   END;WAITKEY                                              
 END; (*QUOTIENT*)                                          
                                                            
BEGIN (* ÈÐ *)                                              
 ANZZ:=0;ANZSP:=0;POKE(-28657,8);                           
 REPEAT                                                     
  WRITELN(CLRSCR,RON,"ÓIMPLEX-ÁLGORITHMUS",CD,CD);         
  WRITELN(CD,RON,"Æ1",ROFF," ÔABLEAU EINGEBEN");            
  WRITELN(CD,RON,"Æ3",ROFF," ÔABLEAU AUSGEBEN");            
  WRITELN(CD,RON,"Æ5",ROFF," ÔABLEAU ITERIEREN");           
  WRITELN(CD,RON,"Æ7",ROFF," ÑUOTIENTEN BILDEN");           
  WRITELN(CD,CD,RON,"Ã",ROFF,"  ÆELDAENDERUNG");            
  WRITELN(CD,RON,"Â",ROFF,"  ÂRUCH ==> ÄEZIMAL");           
  WRITELN(CD,RON,"Ñ",ROFF,"  ÐROGRAMMENDE");                
  REPEAT SYS(-28) UNTIL PEEK(780)<>0;KEY:=PEEK(780);        
  CASE KEY OF                                               
   F1 : BEGIN INIT;EINGABE END;                             
   F3 : AUSGABE;                                            
   F5 : ITERATION;                                          
   F7 : QUOTIENT;                                           
   C  : CHANGEFIELD;                                        
   B  : CALCBRUCH                                           
   ELSE END                                                 
 UNTIL KEY=Q;WRITELN(CLRSCR)                                
END. (* ÈÐ *)