@@ -37,6 +37,7 @@ My accepted leetcode solutions to some of the common interview problems.
 - [Largest Number At Least Twice of Others](problems/src/array/LargestNumberAtLeastTwice.java) (Easy)
 - [Minimum Moves to Equal Array Elements II](problems/src/array/MinimumMovesToEqualArray.java) (Median)
 - [Image Smoother](problems/src/array/ImageSmoother.java) (Easy)
+- [Minimum Index Sum of Two Lists](problems/src/array/MinimumIndexSumOfTwoLists.java) (Easy)
 
 #### [Backtracking](problems/src/backtracking)
 
 
@@ -0,0 +1,81 @@
+package array;
+
+import java.util.ArrayList;
+import java.util.HashMap;
+import java.util.List;
+import java.util.Map;
+
+/**
+ * Created by gouthamvidyapradhan on 11/04/2018.
+ * Suppose Andy and Doris want to choose a restaurant for dinner, and they both have a list of favorite restaurants
+ * represented by strings.
+
+ You need to help them find out their common interest with the least list index sum. If there is a choice tie between
+ answers, output all of them with no order requirement. You could assume there always exists an answer.
+
+ Example 1:
+ Input:
+ ["Shogun", "Tapioca Express", "Burger King", "KFC"]
+ ["Piatti", "The Grill at Torrey Pines", "Hungry Hunter Steakhouse", "Shogun"]
+ Output: ["Shogun"]
+ Explanation: The only restaurant they both like is "Shogun".
+ Example 2:
+ Input:
+ ["Shogun", "Tapioca Express", "Burger King", "KFC"]
+ ["KFC", "Shogun", "Burger King"]
+ Output: ["Shogun"]
+ Explanation: The restaurant they both like and have the least index sum is "Shogun" with index sum 1 (0+1).
+ Note:
+ The length of both lists will be in the range of [1, 1000].
+ The length of strings in both lists will be in the range of [1, 30].
+ The index is starting from 0 to the list length minus 1.
+ No duplicates in both lists.
+
+ Solution:O(N) maintain index of each restaurant in a list using a HashMap, find the min sum of indices and list
+ all the restaurants which match the min sum of indices
+
+ */
+public class MinimumIndexSumOfTwoLists {
+    /**
+     * Main method
+     * @param args
+     */
+    public static void main(String[] args) throws Exception{
+        String[] A1 = {"Shogun", "Tapioca Express", "Burger King", "KFC"};
+        String[] A2 = {"Tapioca Express", "Shogun", "Burger King"};
+        String[] ans = new MinimumIndexSumOfTwoLists().findRestaurant(A1, A2);
+        for(String s : ans){
+            System.out.println(s);
+        }
+    }
+
+    public String[] findRestaurant(String[] list1, String[] list2) {
+        int min = Integer.MAX_VALUE;
+        List<String> result = new ArrayList<>();
+        if(list2.length == 0) return new String[0];
+        Map<String, Integer> index = new HashMap<>();
+        for(int i = 0; i < list2.length; i ++){
+            index.put(list2[i], i);
+        }
+        for(int i = 0; i < list1.length; i ++){
+            String s = list1[i];
+            if(index.containsKey(s)){
+                int sum = i + index.get(s);
+                min = Math.min(min, sum);
+            }
+        }
+
+        for(int i = 0; i < list1.length; i ++){
+            String s = list1[i];
+            if(index.containsKey(s)){
+                int sum = i + index.get(s);
+                if(sum == min){
+                    result.add(s);
+                }
+            }
+        }
+        String[] resArr = new String[result.size()];
+        result.toArray(resArr);
+        return resArr;
+    }
+}