Roman numerals/Decode: Difference between revisions

=={{header|QBasic}}==

<lang QBasic>FUNCTION romToDec (roman$)

num = 0

prenum = 0

FOR i = LEN(roman$) TO 1 STEP -1

x$ = MID$(roman$, i, 1)

n = 0

IF x$ = "M" THEN n = 1000

IF x$ = "D" THEN n = 500

IF x$ = "C" THEN n = 100

IF x$ = "L" THEN n = 50

IF x$ = "X" THEN n = 10

IF x$ = "V" THEN n = 5

IF x$ = "I" THEN n = 1

IF n < preNum THEN num = num - n ELSE num = num + n

preNum = n

NEXT i

romToDec = num

END FUNCTION

!Testing

PRINT "MCMXCIX = "; romToDec("MCMXCIX") '1999

PRINT "MDCLXVI = "; romToDec("MDCLXVI") '1666

PRINT "XXV = "; romToDec("XXV") '25

PRINT "CMLIV = "; romToDec("CMLIV") '954

PRINT "MMXI = "; romToDec("MMXI") '2011</lang>