add 1743

fishercoder1534 · fishercoder1534 · commit a816d0d42ef8 · 2021-01-30T22:10:19.000-08:00
diff --git a/README.md b/README.md
@@ -8,6 +8,7 @@ _If you like this project, please leave me a star._ &#9733;
 
 |  #  |      Title     |   Solutions   | Video  | Difficulty  | Tag                   
 |-----|----------------|---------------|--------|-------------|-------------
+|1743|[Restore the Array From Adjacent Pairs](https://leetcode.com/problems/restore-the-array-from-adjacent-pairs/)|[Solution](../master/src/main/java/com/fishercoder/solutions/_1743.java) ||Medium|Greedy|
 |1742|[Maximum Number of Balls in a Box](https://leetcode.com/problems/maximum-number-of-balls-in-a-box/)|[Solution](../master/src/main/java/com/fishercoder/solutions/_1742.java) ||Easy|Array|
 |1736|[Latest Time by Replacing Hidden Digits](https://leetcode.com/problems/latest-time-by-replacing-hidden-digits/)|[Solution](../master/src/main/java/com/fishercoder/solutions/_1736.java) ||Easy|String, Greedy|
 |1733|[Minimum Number of People to Teach](https://leetcode.com/problems/minimum-number-of-people-to-teach/)|[Solution](../master/src/main/java/com/fishercoder/solutions/_1733.java) ||Medium|Array, Greedy|
diff --git a/src/main/java/com/fishercoder/solutions/_1743.java b/src/main/java/com/fishercoder/solutions/_1743.java
@@ -0,0 +1,48 @@
+package com.fishercoder.solutions;
+
+import java.util.*;
+
+public class _1743 {
+    public static class Solution1 {
+        public int[] restoreArray(int[][] adjacentPairs) {
+            Map<Integer, Integer> map = new HashMap<>();
+            Map<Integer, List<Integer>> map2 = new HashMap<>();
+            for (int[] pair : adjacentPairs) {
+                int num1 = pair[0];
+                int num2 = pair[1];
+                map.put(num1, map.getOrDefault(num1, 0) + 1);
+                map.put(num2, map.getOrDefault(num2, 0) + 1);
+                if (!map2.containsKey(num1)) {
+                    map2.put(num1, new ArrayList<>());
+                }
+                map2.get(num1).add(num2);
+                if (!map2.containsKey(num2)) {
+                    map2.put(num2, new ArrayList<>());
+                }
+                map2.get(num2).add(num1);
+            }
+            int first = Integer.MAX_VALUE;
+            for (int key : map.keySet()) {
+                if (map.get(key) == 1) {
+                    first = key;
+                    break;
+                }
+            }
+            int[] original = new int[map.size()];
+            Set<Integer> set = new HashSet<>();
+            original[0] = first;
+            set.add(first);
+            for (int i = 1; i < map.size(); i++) {
+                int prev = original[i - 1];
+                List<Integer> connected = map2.get(prev);
+                for (int conn : connected) {
+                    if (set.add(conn)) {
+                        original[i] = conn;
+                        break;
+                    }
+                }
+            }
+            return original;
+        }
+    }
+}
