Convert a positive integer between 1 and 3999 to its Roman numeral representation. Roman numerals use seven symbols: I = 1, V = 5, X = 10, L = 50, C = 100, D = 500, and M = 1000. Subtractive notation is used for the values 4, 9, 40, 90, 400, and 900, represented as IV, IX, XL, XC, CD, and CM respectively.
To form a Roman numeral, repeatedly subtract the largest possible value and append the corresponding symbol until the number reaches zero. This greedy strategy produces the standard Roman numeral form.
Examples:
Input: num = 3
Output: 'III'
Explanation: Three ones.
Input: num = 4
Output: 'IV'
Explanation: Subtractive notation: I before V means 4.
Input: num = 9
Output: 'IX'
Explanation: Subtractive notation: I before X means 9.
Input: num = 58
Output: 'LVIII'
Explanation: 50 + 5 + 3 gives L + V + III.
Input: num = 1994
Output: 'MCMXCIV'
Explanation: 1000 + 900 + 90 + 4 gives M + CM + XC + IV.
Welcome to Lightning Challenge!
How It Works
- • Write your solution in the code editor
- • Connect your Salesforce org to test
- • Submit to check if your solution passes
- • Use hints if you get stuck
Contest Alert
Contest runs October 4 - 15. Complete challenges to climb the leaderboard!
Prizes 1 & 2: Salesforce certification exam voucher — won by random drawing, where every point is a ticket. see all prizes
Only the 12 daily challenges shown during this contest count toward points. Earlier dailies don't carry over.