From b45c02e56dfaa32a17c1c2a8ba194f731307d12d Mon Sep 17 00:00:00 2001
From: Akhil Achary <0018akhil@gmail.com>
Date: Thu, 25 May 2023 12:54:34 +0530
Subject: [PATCH] Added Roman to Integer converter program in cpp

---
 algorithms/CPlusPlus/Maths/roman-integer.cpp | 76 ++++++++++++++++++++
 algorithms/CPlusPlus/README.md               |  4 +-
 2 files changed, 78 insertions(+), 2 deletions(-)
 create mode 100644 algorithms/CPlusPlus/Maths/roman-integer.cpp

diff --git a/algorithms/CPlusPlus/Maths/roman-integer.cpp b/algorithms/CPlusPlus/Maths/roman-integer.cpp
new file mode 100644
index 00000000..de67fbaa
--- /dev/null
+++ b/algorithms/CPlusPlus/Maths/roman-integer.cpp
@@ -0,0 +1,76 @@
+#include <iostream>
+#include <unordered_map>
+
+using namespace std;
+
+string intToRoman(int num)
+{
+    // Define the symbols and their corresponding values
+    unordered_map<int, string> symbol_map = {
+        {1000, "M"},
+        {900, "CM"},
+        {500, "D"},
+        {400, "CD"},
+        {100, "C"},
+        {90, "XC"},
+        {50, "L"},
+        {40, "XL"},
+        {10, "X"},
+        {9, "IX"},
+        {5, "V"},
+        {4, "IV"},
+        {1, "I"}};
+
+    // Build the Roman numeral string
+    string roman = "";
+    for (auto &[value, symbol] : symbol_map)
+    {
+        while (num >= value)
+        {
+            roman += symbol;
+            num -= value;
+        }
+    }
+    return roman;
+}
+
+int romanToInt(string s)
+{
+    // Define the symbols and their corresponding values
+    unordered_map<char, int> symbol_map = {
+        {'M', 1000},
+        {'D', 500},
+        {'C', 100},
+        {'L', 50},
+        {'X', 10},
+        {'V', 5},
+        {'I', 1}};
+
+    // Calculate the integer value
+    int value = 0;
+    for (int i = 0; i < s.length(); i++)
+    {
+        if (i > 0 && symbol_map[s[i]] > symbol_map[s[i - 1]])
+        {
+            value += symbol_map[s[i]] - 2 * symbol_map[s[i - 1]];
+        }
+        else
+        {
+            value += symbol_map[s[i]];
+        }
+    }
+    return value;
+}
+
+int main()
+{
+    int num = 1234;
+    string roman = intToRoman(num);
+    cout << num << " in Roman numerals is " << roman << endl;
+
+    string s = "MCCXXXIV";
+    int value = romanToInt(s);
+    cout << s << " in integer value is " << value << endl;
+
+    return 0;
+}
\ No newline at end of file
diff --git a/algorithms/CPlusPlus/README.md b/algorithms/CPlusPlus/README.md
index 064a599b..817e3e1a 100644
--- a/algorithms/CPlusPlus/README.md
+++ b/algorithms/CPlusPlus/README.md
@@ -60,8 +60,6 @@
 - [Floyd Warshall](Graphs/floyd-warshall.cpp)
 - [Detecting Cycle in Directed graph using three colors](Graphs/detecting-cycle-in-a-graph-using-three-color-mechanism.cpp)
 
-
-
 ## Multiplication
 
 - [Karatsuba](Multiplication/karatsuba.cpp)
@@ -82,6 +80,7 @@
 - [Remove Duplicate in Sorted linked list](Linked-Lists/remove-duplicates-in-sorted-linked-list.cpp)
 - [Reverse the linked list using stack](Linked-Lists/reverse-the-list-using-stack.cpp)
 - [Reverse the linked list in groups of K](Linked-Lists/reverse-the-list-in-groups-of-k.cpp)
+
 ## Searching
 
 - [Linear Search](Searching/linear-search.cpp)
@@ -183,6 +182,7 @@
 - [Small numbers](Maths/small-numbers.cpp)
 - [Segmented Sieve](Maths/segmented-sieve-range.cpp)
 - [Binary Power](Maths/binary-power.cpp)
+- [Roman To Integer](Maths/roman-integer.cpp)
 
 # Recursion