Initial data commit

Task/Permutations/Commodore-BASIC/permutations.basic

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+100 INPUT "HOW MANY";N
+110 DIM A(N-1):REM ARRAY TO PERMUTE
+120 DIM K(N-1):REM HOW MANY ITEMS TO PERMUTE (ARRAY AS STACK)
+130 DIM I(N-1):REM CURRENT POSITION IN LOOP (ARRAY AS STACK)
+140 S=0:REM STACK POINTER
+150 FOR I=0 TO N-1
+160 : A(I)=I+1: REM INITIALIZE ARRAY TO 1..N
+170 NEXT I
+180 K(S)=N:S=S+1:GOSUB 200:REM PERMUTE(N)
+190 END
+200 IF K(S-1)>1 THEN 270
+210 REM PRINT OUT THIS PERMUTATION
+220 FOR I=0 TO N-1
+230 : PRINT A(I);
+240 NEXT I
+250 PRINT
+260 RETURN
+270 K(S)=K(S-1)-1:S=S+1:GOSUB 200:S=S-1:REM PERMUTE(K-1)
+280 I(S-1)=0:REM FOR I=0 TO K-2
+290 IF I(S-1)>=K(S-1)-1 THEN 340
+300 J=I(S-1):IF K(S-1) AND 1 THEN J=0:REM ELEMENT TO SWAP BASED ON PARITY OF K
+310 T=A(J):A(J)=A(K(S-1)-1):A(K(S-1)-1)=T:REM SWAP
+320 K(S)=K(S-1)-1:S=S+1:GOSUB 200:S=S-1:REM PERMUTE(K-1)
+330 I(S-1)=I(S-1)+1:GOTO 290:REM NEXT I
+340 RETURN