1// Visit => https://duniya-roman-numeral-converter.netlify.app/
2// Npm Package => https://www.npmjs.com/package/cr-numeral
3
4const convertToRoman = num => {
5    const numbers = [1000, 900, 500, 400, 100, 90, 50, 40, 10, 9, 5, 4, 1]
6    const roman = ['M','CM','D','CD','C','XC','L','XL','X','IX','V','IV','I']
7    let romanNumeral = ''
8
9    // While num is not equal to 0, keep iterating with the value
10    while(num !== 0){
11      	// Find from the numbers array the match for the current number
12        const index = numbers.findIndex(nums => num >= nums)
13        
14        // Keeping pushing the roman value to romanNumeral
15        // Cause the found number from numbers matches the index of its
16        // Corresponding roman below
17        romanNumeral += roman[index]
18      
19      	// Set num to a new value by Substracting the used number from it 
20        num -= numbers[index]
21    }
22
23    return romanNumeral
24}
25
26convertToRoman(3999);
27
28// With love @kouqhar

1romans= [ ['M','D','C'] ,['C','L','X'], ['X','V','I'] ]
2
3
4num = int(input())
5st =""
6div = 100
7t=num
8z =t//1000
9t = t%1000
10if (z>0) :
11  st = st+ z* 'M'
12
13for aplha in romans:
14  z = t//div
15  t%=div
16  if (z in range(1,4)):
17    st+= z*aplha[2]
18  elif (z in range (6,9)):
19    st+= aplha[1] + (z-5)*aplha[2]
20  elif z==4:
21    st+= aplha[2] + aplha[1]
22  elif z==5:
23    st+= aplha[1]
24  elif z==9:
25    st+= aplha[2] + aplha[1]
26  
27  div//=10
28
29print(st)

1// Roman numeral conversions
2fn int_to_roman(num: i32) -> String {
3    let m = [1000, 900, 500, 400, 100, 90, 50, 40, 10, 9, 5, 4, 1];
4    let s = ["M", "CM", "D", "CD", "C", "XC", "L", "XL", "X", "IX", "V", "IV", "I"];
5
6    let (mut num, mut buf) = (num, vec![]);
7    for i in 0..13 {
8        let mut j = num / m[i];
9        num %= m[i];
10        while j > 0 {
11            buf.push(s[i]);
12            j -= 1;
13        }
14    }
15    buf.into_iter().collect()
16}
17
18fn roman_to_int1(s: String) -> i32 {
19    s.chars().rev().fold((0, 0), |(sum, prev), c| {
20            let n = match c {
21                'I' => 1,
22                'V' => 5,
23                'X' => 10,
24                'L' => 50,
25                'C' => 100,
26                'D' => 500,
27                'M' => 1000,
28                _ => panic!("Not a roman numeral")};
29            if n >= prev {              
30                (sum + n, n)
31            } else {
32                (sum - n, n)
33            }
34        }).0
35}
36
37fn main() {
38    let i = 2021;
39    println!("Int {} to Roman {} to Int {}", i, int_to_roman(i), roman_to_int1(int_to_roman(i)));
40}

1/*
2	// This application helps you convert roman numerals to numbers or vice-versa
3*/
4
5// First install the package @ "npm install cr-numeral"
6// Then import or require the package in your application
7const {
8  convertNumberToRoman: cnr,
9  convertRomanToNumber: crn,
10} = require("cr-numeral");
11// OR
12const cnr = require("cr-numeral").convertNumberToRoman;
13const crn = require("cr-numeral").convertRomanToNumber;
14
15// Define your variables
16const number = 2021;
17const numeral = "MMMXXV"; // Case-insensitive
18
19// Use your package/module
20const toRoman = cnr(number);
21const toNumber = crn(numeral);
22
23// Log or use your result
24console.log(toRoman, toNumber);
25
26			// Converting a number to Roman Numeral
27const { convertNumberToRoman } = require('cr-numeral');
28// OR
29const convertNumberToRoman = require('cr-numeral').convertNumberToRoman;
30
31convertNumberToRoman(2021));
32"MMXXI"
33
34convertNumberToRoman(-2021)); // Can not convert a negative number or zero
35"Can not convert Zero or negative numbers!!!"
36
37convertNumberToRoman("na256m"));
38"You must provide only valid numbers!!!"
39
40convertNumberToRoman(false));
41"Cannot use Boolean values!!!"
42
43convertNumberToRoman(true));
44"Cannot use Boolean values!!!"
45
46			// Converting Roman Numeral to Number
47const { convertRomanToNumber } = require('cr-numeral');
48// OR
49const convertRomanToNumber = require('cr-numeral').convertRomanToNumber;
50
51convertRomanToNumber("MMXXI"));
52"2021"
53
54convertRomanToNumber("na256m"));
55"Provide a valid roman character!!!"
56"Cause these are invalid roman numerals : [ N,A,2,5,6 ]"
57
58convertRomanToNumber(6355));
59"You must provide only valid strings!!!"
60
61convertRomanToNumber(false));
62"Cannot use Boolean values!!!"
63
64convertRomanToNumber(true));
65"Cannot use Boolean values!!!"

1function convertToRoman() {
2  let arabic = document.getElementById('arabicNumeral').value; // input value
3  let roman = '';  // variable that will hold the result
4}

1//Java Implementation of Roman To Number
2
3
4public class RomanToNumber {
5	public static int declareIntOfChar(char c)
6	{
7		int val=0;
8		switch(c)
9		{
10		case 'I':
11			val=1;
12			break;
13		case 'V':
14			val=5;
15			break;
16		case 'X':
17			val=10;
18			break;
19		case 'L' : 
20			val=50;
21			break;
22		case 'C' : 
23			val=100;
24			break;
25		case 'D' : 
26			val=500;
27			break;
28		case 'M' : 
29			val=1000;
30			break;
31		default :
32			val=-1;	
33			break;
34		}
35		return val;
36	}
37	public static void main(String[] args) {
38		String s = "XCV";
39		int sum = 0,c1,c2;
40		for(int i=0;i<s.length();i++)
41		{
42			c1=declareIntOfChar(s.charAt(i));
43			if(i+1<s.length())
44			{
45				c2=declareIntOfChar(s.charAt(i+1));
46				if(c1<c2)
47				{
48					sum = sum + c2 - c1;
49					i++;
50				}
51				else
52				{
53					sum = sum + c1;
54				}
55			}
56			else
57			{
58				sum = sum + c1;
59			}
60		}
61		System.out.print(s + " = " + sum);
62	}
63}
64