5  CLEAR 
  10  DIM JP(4096)
  20  PRINT  CHR$ (4);"OPEN DAY5TEXT"
  30  PRINT  CHR$ (4);"READ DAY5TEXT"
  40  ONERR  GOTO 416
  50  INPUT RN
  51 JP(MX) = RN
  52 MX = MX + 1
  53  GOTO 50
  60 PC = 0
  61 ST = 0
  70  IF PC < 0 OR PC >  = MX THEN  GOTO 200
  71 DS = JP(PC)
  72 JP(PC) = DS + 1
  73 PC = PC + DS
  74 ST = ST + 1
  75  GOTO 70
 200  PRINT ST;" STEPS TAKEN"
 201  END 
 404  END 
 416  PRINT  CHR$ (4);"CLOSE DAY5TEXT"
 417  ONERR  GOTO 421
 418 OK = 0
 419  CALL 62248
 420  IF  PEEK (222) = 5 THEN  GOTO 60
 421  PRINT "ERROR: "; PEEK (222)

in the Applesoft BASIC compact format.

included here in Applesoft packed format (day5) and expanded ASCII format
(day5.bas)