Create 13. Roman to Integer.cpp

Author: yash-1104github

13. Roman to Integer.cpp

@@ -0,0 +1,19 @@
+class Solution {
+public:
+    int romanToInt(string s) {
+        unordered_map<char,int>mp =
+        {{'I' , 1},{'V', 5},{'X' , 10},{'L' , 50},{'C' , 100},{'D', 500},{'M', 1000}};
+        
+        int n  = s.size(),total = 0;
+        
+        for(int i = 0 ; i < n; i++){
+            if( i + 1 < n && mp[s[i]] < mp[s[i+1]] ){
+                total -= mp[s[i]];
+            }
+            else{
+                total += mp[s[i]];
+            }
+        }
+        return total;
+    }
+};