I saw this post which shows some VFP code to permute a string. For example, there are 6 permutations of “abc”:

            abc, acb, bac, bca, cab, cba

 

There are n! permutations of a string of length n.

 

 

I dug up some old code that did the same thing in fewer lines.

 

 

nn=0

permute("abcd",0)

 

PROCEDURE permute(cstr,nLev)

      LOCAL nTrylen,i

      nTrylen= LEN(cstr)-nLev

      IF nTryLen = 0

            nn=nn+1

            ?nn,cstr

      ELSE

            FOR i = 1 to nTrylen

                  IF i>1      && swap nlev+1 and nlev+i chars

                        cstr= LEFT(cstr,nlev) + SUBSTR(cstr,nLev+i,1) +;

                              SUBSTR(cstr,nLev+2, i-2)+SUBSTR(cstr,nlev+1,1)+SUBSTR(cstr,nLev+i+1)

                  ENDIF

                  permute(cstr,nlev+1)

            ENDFOR

      ENDIF

RETURN

 

 

 

 

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