XProfan

English

p.specht

with the spending of Kombinationen the wide k from n Elementen is the slippy 'Algorithm T' angesagt; though have I it same combined with 'Algorithm X-7', sodaß one now optional aufsteigende (dflg%=0) or absteigende (dflg%=1) lexikalische Order dial can. on what The combined Indizes verweisen, remaining naturally you give over!

Compile Mark Separation

Window Title "Algorithm X-7 from D. Knuth´s TAOCP 7.2.1.3 p.36 Xercise 7"
' (D)2011/07 Demoware by P. woodpecker
' No warranties whatsoever. Use at your own risk!
' Improved by a decrease-flag (dflg%): 0 = increasing, nonzero = decreasing
var dflg%=0'decreasing order-flag off
Font 2
declare j%,s%,b%[],n%
Start:
CLS rgb(170,255,220)
print " Inc/Decreasing Combinations of k Elements out of N"
print " 0 for aufsteigende, 1 for absteigende Lexikalordnung?: ";:input dflg%
print " n = ";:input n%:print " k = ";:input s%
SetSize b%[],s%
s1:' Initialize

WhileLoop s%:b%[&Loop]=&Loop+n%-s%-1

    EndWhile :j%=1
    s2:' Show result ('Visit' = do something useful)

    Whileloop s%,1,-1

        if dflg%=0:print int(n%-1-b%[&Loop]);'increasing order

            else :print b%[&Loop];'decreasing order

        endif

    EndWhile

    case j%>s%:goto "Halt"' terminate if j>s
    print ",";:case %pos>(60-s%): print

    if %csrlin>20: WaitInput : cls : endif

        s3:' Decrease b(j)
        b%[j%]=b%[j%]-1

        if b%[j%]<j%

            j%=j%+1
            goto "S2"

        endif

        s4:' Reset b%[j%-1]

        while j%>1

            b%[j%-1]=b%[j%]-1
            j%=j%-1

        endwhile

        Goto "S2"
        hold:
        print:print " done. ";
        WaitInput
        Goto "Start"
        END