Task: Sorting algorithms_Shell sort







Python: def shell(seq):
    inc = len(seq) // 2
    while inc:
        for i, el in enumerate(seq[inc:], inc):
            while i >= inc and seq[i - inc] > el:
                seq[i] = seq[i - inc]
                i -= inc
            seq[i] = el
        inc = 1 if inc == 2 else inc * 5 // 11



COBOL:       *******************************************************           
       IDENTIFICATION DIVISION.                                         
      *******************************************************           
       PROGRAM-ID.      SHELLSRT.                                       
      ************************************************************      
      *** SHELLSORT                                           ****      
      ************************************************************      
       ENVIRONMENT DIVISION.                                            
       DATA DIVISION.                                                   
       WORKING-STORAGE SECTION.                                         
       01 II                        PIC S9(008) COMP-5.                 
       01 IJ                        PIC S9(008) COMP-5.                 
       01 IZ                        PIC S9(008) COMP-5.                 
       01 IA                        PIC S9(008) COMP-5.                 
       01 STRT1                     PIC S9(008) COMP-5.                 
       01 STRT2                     PIC S9(008) COMP-5.                 
       01 LGT                       PIC S9(008) COMP-5.                 
       01 ORG                       PIC S9(008) COMP-5.                 
       01 DST                       PIC S9(008) COMP-5.                 
      *                                                                 
       01 GAP                       PIC S9(008) COMP-5.                 
       01 NEGAP                     PIC S9(008) COMP-5.                 
       01 TEMP                      PIC X(32768).                       
       77 KEY-RESULT                PIC X.                              
      *                                                                 
       LINKAGE SECTION.                                                 
       01 SRT-ARRAY                 PIC  X(1000000).                    
       01 NUM-ITEM                  PIC  9(008) COMP-5.                 
       01 SRT-DATA.                                                     
          03 LGT-ITEM               PIC  9(004) COMP-5.                 
          03 SRT-KEYS.                                                  
             05 SRT-KEY OCCURS 10.                                      
                07 K-START         PIC S9(004) COMP-5.                  
                07 K-LENGTH        PIC S9(004) COMP-5.                  
                07 K-ASC           PIC X.                               
      *                                                                 
      *    P R O C E D U R E      D I V I S I O N                       
      *                                                                 
       PROCEDURE DIVISION USING SRT-ARRAY NUM-ITEM SRT-DATA.                
                                                                        
           COMPUTE GAP = NUM-ITEM / 2.                                  
           PERFORM UNTIL GAP < 1                                        
              COMPUTE NEGAP = GAP * -1                                  
              PERFORM VARYING II FROM GAP BY 1                          
                        UNTIL II GREATER  NUM-ITEM                      
                 MOVE ' ' TO KEY-RESULT                                 
                 COMPUTE ORG = (II - 1) * LGT-ITEM + 1                  
                 MOVE SRT-ARRAY(ORG:LGT-ITEM) TO TEMP(1:LGT-ITEM)       
                 PERFORM VARYING IJ FROM II BY NEGAP                    
                           UNTIL IJ NOT GREATER  GAP                    
                              OR (KEY-RESULT NOT EQUAL '<' AND ' ')     
                    COMPUTE IA = IJ - GAP                               
                    IF IA < 1                                           
                       MOVE 1 TO IA                                     
                    END-IF                                              
                    PERFORM COMPARE-KEYS                                
                    IF KEY-RESULT = '<'                                 
                       COMPUTE ORG = (IA - 1) * LGT-ITEM + 1            
                       COMPUTE DST = (IJ - 1) * LGT-ITEM + 1            
                       MOVE SRT-ARRAY(ORG:LGT-ITEM)                     
                         TO SRT-ARRAY(DST:LGT-ITEM)                     
                       COMPUTE DST = (IA - 1) * LGT-ITEM + 1            
                       MOVE TEMP(1:LGT-ITEM) TO SRT-ARRAY(DST:LGT-ITEM) 
                    END-IF                                              
                 END-PERFORM                                            
              END-PERFORM                                               
              IF GAP = 2                                                
                 MOVE 1 TO GAP                                          
              ELSE                                                      
                 COMPUTE GAP = GAP / 2.2                                
              END-IF                                                    
           END-PERFORM.                                                 
           GOBACK.                                                      
      *                                                                 
       COMPARE-KEYS.                                                    
           MOVE ' ' TO KEY-RESULT                                       
           PERFORM VARYING IZ FROM 1 BY 1                               
                     UNTIL IZ GREATER 10                                
                        OR (KEY-RESULT NOT EQUAL '=' AND ' ')           
              IF SRT-KEY(IZ) GREATER LOW-VALUES                         
                 COMPUTE STRT1 = (IJ - 1) * LGT-ITEM + K-START(IZ)      
                 COMPUTE STRT2 = (IA - 1) * LGT-ITEM + K-START(IZ)      
                 MOVE K-LENGTH(IZ) TO LGT                               
                 IF SRT-ARRAY(STRT1:LGT) > SRT-ARRAY(STRT2:LGT) AND     
                    K-ASC(IZ) EQUAL 'A'                                 
                 OR SRT-ARRAY(STRT1:LGT) < SRT-ARRAY(STRT2:LGT) AND     
                    K-ASC(IZ) EQUAL 'D'                                 
                    MOVE '>' TO KEY-RESULT                              
                 END-IF                                                 
                 IF SRT-ARRAY(STRT1:LGT) < SRT-ARRAY(STRT2:LGT) AND     
                    K-ASC(IZ) EQUAL 'A'                                 
                 OR SRT-ARRAY(STRT1:LGT) > SRT-ARRAY(STRT2:LGT) AND     
                    K-ASC(IZ) EQUAL 'D'                                 
                    MOVE '<' TO KEY-RESULT                              
                 END-IF                                                 
              END-IF                                                    
           END-PERFORM.                                                 
           IF KEY-RESULT = ' '                                          
              MOVE '=' TO KEY-RESULT                                    
           END-IF.