Merge pull request #112 from stubborn-akshat/patch-2

Roman_to_Integer.java

Author: PawanJaiswal08

13. Roman to Integer

@@ -0,0 +1,34 @@
+class Solution {
+    public int romanToInt(String s) {
+        
+        HashMap<Character,Integer> map=new HashMap<>();
+        map.put('I',1);
+        map.put('V',5);
+        map.put('X',10);
+        map.put('L',50);
+        map.put('C',100);
+        map.put('D',500);
+        map.put('M',1000);
+    
+    int sum=0;
+    for(int i=0;i<s.length();i++){
+        char ch=s.charAt(i);
+        int a=map.get(ch);
+        
+        if(i+1<s.length()){
+            int b=map.get(s.charAt(i+1));
+            
+            if(a>=b){
+                sum=sum+a;
+            }
+            else{
+                sum=sum-a;
+            }
+        }
+        else{
+            sum=sum+a;
+        }
+    }
+    return sum;
+    }
+}