REM Roman numerals/Encode
DIM Weights(12)
DIM Symbols$(12)
DATA 1000, "M", 900, "CM", 500, "D", 400, "CD", 100, "C", 90, "XC", 50, "L"
DATA 40, "XL", 10, "X", 9, "IX", 5, "V", 4, "IV", 1, "I"
REM 3888 or MMMDCCCLXXXVIII (15 chars) is the longest string properly encoded
REM with these symbols.
FOR J = 0 TO 12
  READ Weights(J)
  READ Symbols$(J)
NEXT J

AValue = 1990
GOSUB ToRoman:
PRINT Roman$
REM MCMXC
AValue = 2022
GOSUB ToRoman:
PRINT Roman$
REM MMXXII
AValue = 3888
GOSUB ToRoman:
PRINT Roman$
REM MMMDCCCLXXXVIII
END

ToRoman:
REM Result: Roman$
Roman$ = ""
I = 0
Loop:
  IF (I > 12 THEN ExitToRoman:
  IF AValue <= 0 THEN ExitToRoman:
  WHILE AValue >= Weights(I)
    Roman$ = Roman$ + Symbols$(I)
    AValue = AValue - Weights(I)
  WEND
  I = I + 1
  GOTO Loop:
ExitToRoman:
RETURN