LeetCode: Minimum Index Sum of Two Lists

LeetCode: Minimum Index Sum of Two Lists

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:

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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:

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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:

  1. The length of both lists will be in the range of [1, 1000].
  2. The length of strings in both lists will be in the range of [1, 30].
  3. The index is starting from 0 to the list length minus 1.
  4. No duplicates in both lists.
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public class Solution {
    public String[] findRestaurant(String[] list1, String[] list2) {
        Map<String, Integer> m1 = new HashMap<>();
        Map<String, Integer> m2 = new HashMap<>();

        for (int i = 0; i < list1.length; i++) {
            m1.put(list1[i], i);
        }
        for (int i = 0; i < list2.length; i++) {
            m2.put(list2[i], i);
        }

        for (Map.Entry<String, Integer> entry : m1.entrySet()) {
            if (m2.containsKey(entry.getKey())) {
                m1.put(entry.getKey(), entry.getValue() + m2.get(entry.getKey()));
            } else {
                m1.put(entry.getKey(), Integer.MAX_VALUE);
            }
        }
        int minValue = m1.values().stream().mapToInt(Integer::intValue).min().orElse(-1);
        List<String> result = new ArrayList<>();

        for (Map.Entry<String, Integer> entry : m1.entrySet()) {
            if (entry.getValue() == minValue) {
                result.add(entry.getKey());
            }
        }

        return result.toArray(new String[result.size()]);
    }
}