update

Author: genkimaru

src/main/java/com/leetcode/hash/Anagram.java

@@ -0,0 +1,41 @@
+package com.leetcode.hash;
+
+import java.sql.Array;
+import java.util.*;
+
+/**
+ *
+ *
+ * keyword :  hash , group
+ */
+
+public class Anagram {
+
+    public List<List<String>> groupAnagrams(String[] strs) {
+        List<List<String>>  result = new ArrayList<>();
+        HashMap<String,List<String>> map = new HashMap<String,List<String>>();
+
+        for (int i = 0; i < strs.length; i++) {
+            char[] temp = strs[i].toCharArray();
+            Arrays.sort(temp);
+            String sortedStr = String.valueOf(temp);
+            Set<String> set = map.keySet();
+
+            if(set.contains(sortedStr)){
+                map.get(sortedStr).add(strs[i]);
+            }else{
+                ArrayList<String> list = new ArrayList<>();
+                list.add(strs[i]);
+                map.put(sortedStr , list );
+            }
+        }
+        result.addAll(map.values());
+        return result;
+    }
+
+
+    public static void main(String[] args) {
+        String[] strs = {"eat", "tea", "tan", "ate", "nat", "bat"};
+        List<List<String>> lists = new Anagram().groupAnagrams(strs);
+    }
+}

src/main/java/com/leetcode/hash/ConsecutiveSequence.java

@@ -0,0 +1,32 @@
+package com.leetcode.hash;
+
+import java.util.*;
+
+public class ConsecutiveSequence {
+
+    public int longestConsecutive(int[] nums) {
+
+        // sort the array using Arrays.sort()
+        Arrays.sort(nums);
+        int count = 1;
+        int max = 1;
+        for (int i = 1; i < nums.length; i++) {
+            if (nums[i] - nums[i - 1] == 1) {
+                count++;
+            } else {
+                // record last max count.
+                max = Math.max(max, count);
+                count = 1;
+            }
+        }
+        return Math.max(max, count);
+    }
+
+
+    public static void main(String[] args) {
+
+        int[] nums = {100, 4, 200, 1, 3, 2};
+        int i = new ConsecutiveSequence().longestConsecutive(nums);
+        System.out.println(i);
+    }
+}

src/main/java/com/leetcode/hash/TwoSumS.java

@@ -3,23 +3,27 @@
 import java.util.HashMap;
 import java.util.Map;
 
+/**
+ *  put the ele and index of array into a hashmap.
+ *
+ */
 public class TwoSumS {
 
-    public int[] twoSun(int[] nums , int target){
+    public int[] twoSun(int[] nums, int target) {
         Map<Integer, Integer> map = new HashMap<>();
         for (int i = 0; i < nums.length; i++) {
-            if (map.containsKey(target-nums[i])) {
-                return new int[]{i, map.get(target-nums[i])};
+            if (map.containsKey(target - nums[i])) {
+                return new int[]{i, map.get(target - nums[i])};
             }
             map.put(nums[i], i);
         }
         return new int[]{};
     }
 
     public static void main(String[] args) {
-        int[] arr = {2,5,7,9};
+        int[] arr = {2, 5, 7, 9};
         int[] ints = new TwoSumS().twoSun(arr, 7);
-        for(int i : ints){
+        for (int i : ints) {
             System.out.println(i);
         }