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Convert an Integer to a Roman Numeral

Certification: Basic Level Accuracy: 82.93% Submissions: 41 Points: 10

Write a Python program that converts an integer to a Roman numeral. Roman numerals are represented by combinations of letters from the Latin alphabet (I, V, X, L, C, D, M). The program should handle integers from 1 to 3999.

Example 1
    

  • Input: num = 58
    • 

  • Output: "LVIII"
    • 

  • Explanation: 
      

    • Step 1: Create a mapping of integer values to Roman symbols.
      • 

    • Step 2: 50 is represented as 'L'.
      • 

    • Step 3: 8 is represented as 'VIII' (5 + 3).
      • 

    • Step 4: Combine them to get "LVIII".
      • 

    • Step 5: Return the resulting Roman numeral.
      • 

    •
Example 2
    

  • Input: num = 1994
    • 

  • Output: "MCMXCIV"
    • 

  • Explanation: 
      

    • Step 1: Create a mapping of integer values to Roman symbols, including subtractive combinations.
      • 

    • Step 2: 1000 is represented as 'M'.
      • 

    • Step 3: 900 is represented as 'CM' (1000-100).
      • 

    • Step 4: 90 is represented as 'XC' (100-10).
      • 

    • Step 5: 4 is represented as 'IV' (5-1).
      • 

    • Step 6: Combine them to get "MCMXCIV".
      • 

    • Step 7: Return the resulting Roman numeral.
      • 

    •
Constraints
    

  • 1 ≤ num ≤ 3999
    • 

  • Time Complexity: O(1) since there is a finite set of Roman numeral symbols
    • 

  • Space Complexity: O(1)
    •
StringsNumberListEYAdobe
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Hint
Solution

Solution Hints

    
  
  • Create two lists: one for values and one for corresponding Roman symbols
    • 
  
  • Start from the largest value and work down to the smallest
    • 
  
  • Use integer division and modulo to find the number of times each symbol is used
    • 
  
  • Append the appropriate number of symbols to the result string
    • 
  
  • Handle special cases: 4, 9, 40, 90, 400, 900 with their own symbols
    • 
  
  • Use a greedy approach to choose the largest possible symbol at each step
    •

Steps to solve by this approach:

 Step 1: Define ordered lists of integer values and their corresponding Roman numerals.

 Step 2: Initialize an empty string to store the Roman numeral result.

 Step 3: Iterate through the values list and their corresponding numerals.

 Step 4: Calculate how many times each value fits into the remaining number using integer division.

 Step 5: Append the corresponding numeral that many times to the result string.

 Step 6: Update the number by taking the remainder after division.

 Step 7: Return the completed Roman numeral string.

Submitted Code :