solve 49.group-anagrams

Author: andavid

vscode/49.group-anagrams.java

@@ -0,0 +1,65 @@
+/*
+ * @lc app=leetcode id=49 lang=java
+ *
+ * [49] Group Anagrams
+ *
+ * https://leetcode.com/problems/group-anagrams/description/
+ *
+ * algorithms
+ * Medium (46.25%)
+ * Likes:    1856
+ * Dislikes: 120
+ * Total Accepted:    370.8K
+ * Total Submissions: 768.1K
+ * Testcase Example:  '["eat","tea","tan","ate","nat","bat"]'
+ *
+ * Given an array of strings, group anagrams together.
+ *
+ * Example:
+ *
+ *
+ * Input: ["eat", "tea", "tan", "ate", "nat", "bat"],
+ * Output:
+ * [
+ * ⁠ ["ate","eat","tea"],
+ * ⁠ ["nat","tan"],
+ * ⁠ ["bat"]
+ * ]
+ *
+ * Note:
+ *
+ *
+ * All inputs will be in lowercase.
+ * The order of your output does not matter.
+ *
+ *
+ */
+class Solution {
+  public List<List<String>> groupAnagrams(String[] strs) {
+    if (strs.length == 0) return new ArrayList();
+
+    Map<String, List<String>> map = new HashMap<>();
+    int[] count = new int[26];
+
+    for (String str : strs) {
+      Arrays.fill(count, 0);
+      for (char ch : str.toCharArray()) {
+        count[ch - 'a']++;
+      }
+
+      StringBuilder sb = new StringBuilder();
+      for (int i = 0; i < count.length; i++) {
+        sb.append("#");
+        sb.append(count[i]);
+      }
+      String key = sb.toString();
+
+      if (!map.containsKey(key)) {
+        map.put(key, new ArrayList());
+      }
+      map.get(key).add(str);
+    }
+
+    return new ArrayList(map.values());
+  }
+}