March LeetCoding Challenge 2021 — Day 10: Integer to Roman

Today, we will solve the 10th problem of the March LeetCoding Challenge.

Problem Statement

Roman numerals are represented by seven different symbols: I, V, X, L, C, D and M.

Symbol       Value
I             1
V             5
X             10
L             50
C             100
D             500
M             1000

For example, 2 is written as II in Roman numeral, just two one's added together. 12 is written as XII, which is simply X + II. The number 27 is written as XXVII, which is XX + V + II.

Roman numerals are usually written largest to smallest from left to right. However, the numeral for four is not IIII. Instead, the number four is written as IV. Because the one is before the five we subtract it making four. The same principle applies to the number nine, which is written as IX. There are six instances where subtraction is used:

• I can be placed before V (5) and X (10) to make 4 and 9.
• X can be placed before L (50) and C (100) to make 40 and 90.
• C can be placed before D (500) and M (1000) to make 400 and 900.

Given an integer, convert it to a roman numeral.

Example 1:

Input: num = 3
Output: "III"

Example 2:

Input: num = 4
Output: "IV"

Example 3:

Input: num = 9
Output: "IX"

Example 4:

Input: num = 58
Output: "LVIII"
Explanation: L = 50, V = 5, III = 3.

Example 5:

Input: num = 1994
Output: "MCMXCIV"
Explanation: M = 1000, CM = 900, XC = 90 and IV = 4.

Solution

This is an amazing problem. We have to convert an integer to its roman equivalent number. Go through the problem statement carefully. You will get to know how to represent an integer in roman.

So we can say that we will have roman equivalent for these numbers. numbers = [1000,900,500,400,100,90,50,40,10,9,5,4,1] , for these numbers, we have there corresponding roman values = [M,CM,D,CD,C,XC,L,XL,X,IX,V,IV,I] .

We can assign the maximum possible equivalent roman characters for the integer value.

The code is given below.

The code can be found here

sksaikia/LeetCode

Check out my other posts on March LeetCoding Challenge 2021.

1. March LeetCoding Challenge — Day 1 — Distribute Candies
2. March LeetCoding Challenge — Day 2 — Set Mismatch
3. March LeetCoding Challenge — Day 3 — Missing Number
4. March LeetCoding Challenge — Day 4 — Intersection of Two Linked Lists
5. March LeetCoding Challenge — Day 5 — Average of Levels in Binary Tree
6. March LeetCoding Challenge — Day 6 — Short Encoding of Words
7. March LeetCoding Challenge — Day 8— Remove Palindromic Subsequences