100 DEFINT A-Z:INPUT "a,b ";A,B:N=A*B:TIM#=TIMER
110 DIM B(N),A(N,N),U(N,N),V(N),P(N),T(N)
120  FOR X=0 TO B-1:FOR Y=0 TO A-1:XY=X*A+Y+1
130  FOR U=0 TO B-1:FOR V=0 TO A-1:UV=U*A+V+1
140  DX=X-U:DY=Y-V:IF DX*DX+DY*DY=5 THEN A(XY,UV)=1
150  NEXT V,U,Y,X
160 OPEN "o",3,"p":PRINT#3,"1,1":CLOSE 3
170  FOR S=1 TO N:FOR I=1 TO S:U(S,I)=0:NEXT
175  FOR I=S+1 TO N:FOR J=1 TO N:U(S,J)=U(S,J)+A(I,J):NEXT J,I
180  FOR I=S+1 TO N:U(S,I)=N+1:NEXT I,S
190 FOR S=2 TO N-1
200  VON0=1:WHILE U(S-1,VON0)=0:VON0=VON0+1:WEND
210  VON=1:WHILE U(S,VON)=0:VON=VON+1:WEND
220 OPEN "i",2,"p":OPEN "o",3,"q"
230 ' --------------------------------------
240 INPUT#2,O$,Z#:FOR I=VON0 TO S-1:B(I)=ASC(MID$(O$,I-VON0+1,1))-48:NEXT
250  FOR I=VON0 TO S:T(I)=B(I):NEXT:T(S)=1:GOSUB 530
260   P=1:FOR I=1 TO 22:P(I)=0:V(I)=0:NEXT:FOR I=VON0 TO S
270   IF B(I)>1 AND V(B(I))=0 THEN P=P+1:V(B(I))=I
280   IF B(I)>1 AND V(B(I))>0 THEN P(I)=V(B(I)):P(V(B(I)))=I
290   NEXT I
300  D=0:FOR U=VON0 TO S:IF B(U)=0 OR A(U,S)=0 THEN 350
310  D=D+1:Q(D)=U
320  FOR I=VON0 TO S:T(I)=B(I):NEXT
330  IF B(U)=1 THEN T(U)=P+1:T(S)=P+1:GOSUB 530
340  IF B(U)>1 THEN T(S)=B(U):T(U)=0:GOSUB 530
350  NEXT U
360 FOR I=1 TO D:FOR J=I+1 TO D:U=Q(I):V=Q(J):IF B(U)>1 AND P(U)=V THEN 420
370 FOR K=VON0 TO S:T(K)=B(K):NEXT
380 IF B(U)=1 AND B(V)=1 THEN T(U)=P+1:T(V)=P+1:GOSUB 530
390 IF B(U)>1 AND B(V)>1 THEN T(V)=0:T(P(V))=T(U):T(U)=0:GOSUB 530
400 IF B(U)>1 AND B(V)=1 THEN T(V)=B(U):T(U)=0:GOSUB 530
410 IF B(U)=1 AND B(V)>1 THEN T(U)=B(V):T(V)=0:GOSUB 530
420 NEXT J,I
430  IF EOF(2)=0 THEN 240 ELSE CLOSE
440  SHELL "sort q p"
450    OPEN "i",2,"p":OPEN "o",3,"q":INPUT#2,M$,S#:S1#=1:S2#=0
460    IF EOF(2) THEN 500
470    INPUT#2,A$,Z#
480    IF A$=M$ THEN S#=S#+Z#:GOTO 460
490    PRINT#3,M$;",";S#:M$=A$:S1#=S1#+1:S2#=S2#+S#:S#=Z#:GOTO 460
500    PRINT#3,M$;",";S#:S2#=S2#+S#:CLOSE:SHELL "del p":SHELL "ren q p"
510    PRINT S;S1#;S2#;TIMER-TIM#
520 NEXT S:END
530 ' ---------------correct pathstructure and print-----------
540 Q=0:FOR K=VON0 TO VON-1:Q=Q+T(K):NEXT:IF Q THEN RETURN
550 G=0:B$="":K1=1:FOR K=0 TO 18:V(K)=0:NEXT
560 FOR K=VON TO S:T=T(K):IF T<2 THEN B=T:GOTO 580
570 IF V(T) THEN B=V(T) ELSE K1=K1+1:B=K1:V(T)=K1
580 B$=B$+CHR$(48+B):IF (U(S,K)=0 AND B>0) OR (B=1 AND U(S,K)<2) THEN G=1
590 NEXT:IF G=0 THEN PRINT#3,B$;",";Z#
600 RETURN