Permutations/Derangements: Difference between revisions

Content added Content deleted

Inline

@@ Line 2,393: / Line 2,393: @@
 =={{header|PureBasic}}==
+Brute Force
-{{incomplete|PureBasic|Missing the subfactorial !n.}}
-Brute Force: Tested up to n=10
 <lang PureBasic>
 Procedure.q perm(n)
-if n=0:ProcedureReturn 1:endif
+If n=0:ProcedureReturn 1:EndIf
-if n=1:ProcedureReturn 0:endif
+If n=1:ProcedureReturn 0:EndIf
 ProcedureReturn (perm(n-1)+perm(n-2))*(n-1)
 EndProcedure
 factFile.s="factorials.txt"
 tempFile.s="temp.txt"
@@ Line 2,409: / Line 2,407: @@
 DeleteFile(tempFile.s)
 DeleteFile(drngFile.s)
 n=4
 ; create our storage file
 f.s=factFile.s
-If CreateFile(2113,f.s)
+If CreateFile(0,f.s)
-WriteStringN(2113,"1.2")
+WriteStringN(0,"1.2")
-WriteStringN(2113,"2.1")
+WriteStringN(0,"2.1")
-CloseFile(2113)
+CloseFile(0)
 Else
 Debug "not createfile :"+f.s
 EndIf
-showfactorial=#FALSE
+showfactorial=#False
-if showfactorial
+If showfactorial
 ; cw("nfactorial n ="+str(n))
-Debug "nfactorial n ="+str(n)
+Debug "nfactorial n ="+Str(n)
+EndIf
-endif
 ; build up the factorial combinations
-for l=1 to n-2
+For l=1 To n-2
-gosub nfactorial
+Gosub nfactorial
+Next
-next
 ; extract the derangements
 ; cw("derangements["+str(perm(n))+"] for n="+str(n))
-Debug "derangements["+str(perm(n))+"] for n="+str(n)
+Debug "derangements["+Str(perm(n))+"] for n="+Str(n)
-gosub derangements
+Gosub derangements
 ; cw("")
 Debug ""
 ; show the first 20 derangements
-for i=0 to 20
+For i=0 To 20
 ; cw("derangements["+str(perm(i))+"] for n="+str(i))
-Debug "derangements["+str(perm(i))+"] for n="+str(i)
+Debug "derangements["+Str(perm(i))+"] for n="+Str(i)
+Next
-next
-end
+End
 derangements:
 x=0
-If ReadFile(2112,factFile.s) and CreateFile(2113,drngFile.s)
+If ReadFile(0,factFile.s) And CreateFile(1,drngFile.s)
+Repeat
-repeat
-r.s = ReadString(2112)
+r.s = ReadString(0)
 cs=CountString(r.s,".")
-if cs
+If cs
 hit=0
 t.s=""
 ; scan for numbers at their index
-for i=1 to cs+1
+For i=1 To cs+1
 s.s=StringField(r.s,i,".")
 t.s+s.s+"."
-if val(s.s)=i:hit+1:endif
+If Val(s.s)=i:hit+1:EndIf
+Next
-next
-t.s=rtrim(t.s,".")
+t.s=RTrim(t.s,".")
 ; show only those which are valid
-if not hit
+If Not hit
 x+1
 ; cw(t.s+" "+str(x))
-Debug t.s+" "+str(x)
+Debug t.s+" "+Str(x)
-WriteStringN(2113,t.s+" "+str(x))
+WriteStringN(1,t.s+" "+Str(x))
+EndIf
-endif
+EndIf
-endif
+Until Eof(0)
-until eof(2112)
-CloseFile(2112)
+CloseFile(0)
-CloseFile(2113)
+CloseFile(1)
 Else
 Debug "not readfile :"+factFile.s
@@ Line 2,481: / Line 2,480: @@
 ; cw("")
 Debug ""
+Return
-return
 nfactorial:
 x=0
-If ReadFile(2112,factFile.s) and CreateFile(2113,tempFile.s)
+If ReadFile(0,factFile.s) And CreateFile(1,tempFile.s)
+Repeat
-repeat
-r.s = ReadString(2112)
+r.s = ReadString(0)
 cs=CountString(r.s,".")
-if cs
+If cs
-for j=1 to cs+2
+For j=1 To cs+2
 t.s=""
-for i=1 to cs+1
+For i=1 To cs+1
 s.s=StringField(r.s,i,".")
-if i=j
+If i=j
-t.s+"."+str(cs+2)+"."+s.s
+t.s+"."+Str(cs+2)+"."+s.s
+Else
-else
 t.s+"."+s.s
+EndIf
-endif
+Next
-next
-if j=cs+2:t.s+"."+str(cs+2):endif
+If j=cs+2:t.s+"."+Str(cs+2):EndIf
-t.s=trim(t.s,".")
+t.s=Trim(t.s,".")
 x+1
-if cs+2=n and showfactorial
+If cs+2=n And showfactorial
 ; cw(t.s+" "+str(x))
-Debug t.s+" "+str(x)
+Debug t.s+" "+Str(x)
+EndIf
-endif
-WriteStringN(2113,t.s)
+WriteStringN(1,t.s)
+Next
-next
+EndIf
-endif
+Until Eof(0)
-until eof(2112)
-CloseFile(2112)
+CloseFile(0)
-CloseFile(2113)
+CloseFile(1)
 Else
 Debug "not readfile :"+factFile.s
@@ Line 2,519: / Line 2,518: @@
 CopyFile(tempFile.s,factFile.s)
 DeleteFile(tempFile.s)
+Return
-return
 </lang>