Task: Recaman's sequence








VB: 
	nx=15
	h=1000
	Wscript.StdOut.WriteLine "Recaman
	Wscript.StdOut.WriteLine recaman("seq",nx)
	Wscript.StdOut.WriteLine "The first duplicate number is: " & recaman("firstdup",0)
	Wscript.StdOut.WriteLine "The number of terms to complete the range 0--->"& h &" is: "& recaman("numterm",h)
	Wscript.StdOut.Write vbCrlf&".../...": zz=Wscript.StdIn.ReadLine()
	
function recaman(op,nn)
	Dim b,d,h
	Set b = CreateObject("Scripting.Dictionary")
	Set d = CreateObject("Scripting.Dictionary")
    list="0" : firstdup=0
	if op="firstdup" then
		nn=1000 : firstdup=1
	end if
	if op="numterm" then
		h=nn : nn=10000000 : numterm=1
	end if
	ax=0  
	b.Add 0,1  
	s=0
	for n=1 to nn-1
        an=ax-n
		if an<=0 then 
			an=ax+n
		elseif b.Exists(an) then 
			an=ax+n
		end if
		ax=an  
		if not b.Exists(an) then b.Add an,1  
		if op="seq" then
			list=list&" "&an
		end if
		if firstdup then
			if d.Exists(an) then
				recaman="a("&n&")="&an
				exit function
			else
				d.Add an,1  
			end if
		end if
		if numterm then
			if an<=h then
				if not d.Exists(an) then
					s=s+1
					d.Add an,1  
				end if
				if s>=h then
					recaman=n
					exit function
				end if
			end if
		end if
	next 
	recaman=list
end function 


COBOL:         IDENTIFICATION DIVISION.
        PROGRAM-ID. RECAMAN.
        
        DATA DIVISION.
        WORKING-STORAGE SECTION.
        01 RECAMAN-SEQUENCE COMP.
           02 A     PIC 999 OCCURS 99 TIMES INDEXED BY I.
           02 N     PIC 999 VALUE 0.
           
        01 VARIABLES COMP.
           02 ADDC  PIC S999.
           02 SUBC  PIC S999.
           02 SPTR  PIC 99 VALUE 1.
           
        01 OUTPUT-FORMAT.
           02 OUTI  PIC Z9.
           02 OUTN  PIC BZ9.
           02 OUTS  PIC X(79).
           
        PROCEDURE DIVISION.
        BEGIN.
            PERFORM GENERATE-NEXT-ITEM 15 TIMES.
            PERFORM COLLATE-ITEM VARYING I FROM 1 BY 1
                UNTIL I IS GREATER THAN 15.
            DISPLAY 'First 15 items:' OUTS.
        
        FIND-REPEATING.
            PERFORM GENERATE-NEXT-ITEM.
            SET I TO 1.
            SEARCH A VARYING I
                WHEN I IS NOT LESS THAN N 
                    NEXT SENTENCE
                WHEN A(I) IS EQUAL TO A(N)
                    SUBTRACT 1 FROM N GIVING OUTI
                    MOVE A(N) TO OUTN
                    DISPLAY 'First repeated item: A(' OUTI ') =' OUTN
                    STOP RUN.
            GO TO FIND-REPEATING.
        
        GENERATE-NEXT-ITEM.
            IF N IS EQUAL TO ZERO
                MOVE ZERO TO A(1)
            ELSE
                ADD N, A(N) GIVING ADDC
                SUBTRACT N FROM A(N) GIVING SUBC
                IF SUBC IS NOT GREATER THAN ZERO
                    MOVE ADDC TO A(N + 1)
                ELSE
                    SET I TO 1
                    SEARCH A VARYING I
                        WHEN I IS NOT LESS THAN N
                            MOVE SUBC TO A(N + 1)
                        WHEN A(I) IS EQUAL TO SUBC
                            MOVE ADDC TO A(N + 1).
            ADD 1 TO N.
            
        COLLATE-ITEM.
            MOVE A(I) TO OUTN.
            STRING OUTN DELIMITED BY SIZE INTO OUTS WITH POINTER SPTR.