String and Math Done

Author: omprashantjain

4 Math/RomanToInteger.java …code 13 Roman to Integer using Math.java4 Math/RomanToInteger.java renamed to 1 Leetcode Easy Problems/Leetcode 13 Roman to Integer using Math.java 4 Math/RomanToInteger.java renamed to 1 Leetcode Easy Problems/Leetcode 13 Roman to Integer using Math.java

@@ -0,0 +1,36 @@
+import java.util.*;
+
+class Solution {
+  private final Map<Character, Integer> SYMBOLS = new HashMap<>();
+  {
+      SYMBOLS.put('I', 1);
+      SYMBOLS.put('V', 5);
+      SYMBOLS.put('X', 10);
+      SYMBOLS.put('L', 50);
+      SYMBOLS.put('C', 100);
+      SYMBOLS.put('D', 500);
+      SYMBOLS.put('M', 1000);
+  }
+
+  public int romanToInt(String roman) {
+      int result = 0;
+      for (int i = 0; i < roman.length(); i++) {
+          char current = roman.charAt(i);
+          int currValue = SYMBOLS.get(current);
+          int nextValue = 0;
+
+          if (i + 1 < roman.length()) {
+              char nextChar = roman.charAt(i+1);
+              nextValue = SYMBOLS.get(nextChar);
+          }
+
+          if (nextValue > currValue) {
+              result += (nextValue - currValue);
+              i++;
+          } else {
+              result += currValue;
+          }
+      }
+      return result;
+  }
+}