add 189 java

Author: yennj12

README.md

@@ -228,7 +228,7 @@
 157 | [Read N Characters Given Read4](https://leetcode.com/problems/read-n-characters-given-read4/) |  [Python](./leetcode_python/Array/read-n-characters-given-read4.py) | _O(n)_ | _O(1)_ | Easy |🔒, buffer, `google`, `amazon`, `fb`| AGAIN**** (3)
 163 | [Missing Ranges](https://leetcode.com/problems/missing-ranges/)| [Python](./leetcode_python/Array/missing-ranges.py),  [Java](./leetcode_java/src/main/java/LeetCodeJava/Array/MissingRanges.java) | _O(n)_  | _O(1)_ | Medium| two pointer, 🔒, `google`, `amazon` | OK******* (4)
 169 | [Majority Element](https://leetcode.com/problems/majority-element/) |[Python](./leetcode_python/Array/majority-element.py), [Java](./leetcode_java/src/main/java/LeetCodeJava/Array/MajorityElement.java) | _O(n)_ | _O(1)_ | Easy |`amazon`| OK*
-189 | [Rotate Array](https://leetcode.com/problems/rotate-array/)   | [Python](./leetcode_python/Array/rotate-array.py) | _O(n)_ | _O(1)_  | Medium |array, k % len(nums), good basic, `amazon`| OK* (7) (but again)
+189 | [Rotate Array](https://leetcode.com/problems/rotate-array/)| [Python](./leetcode_python/Array/rotate-array.py), [Java](./leetcode_java/src/main/java/LeetCodeJava/Array/RotateArray.java)| _O(n)_ | _O(1)_  | Medium |array, k % len(nums), good basic, `amazon`| OK* (7) (but again)
 209 | [Minimum Size Subarray Sum](https://leetcode.com/problems/minimum-size-subarray-sum/) | [Python](./leetcode_python/Array/minimum-size-subarray-sum.py) | _O(n)_ | _O(1)_ | Medium | good basic, sliding window, `Binary Search`, `trick`,`2 pointers`, `fb` | OK********** (5) (but again)
 215 | [Kth Largest Element in an Array](https://leetcode.com/problems/kth-largest-element-in-an-array/) | [Python](./leetcode_python/Array/kth-largest-element-in-an-array.py), [Java](./leetcode_java/src/main/java/LeetCodeJava/Array/KthLargestElementInAnArray.java) | _O(n)_ ~ _O(n^2)_ | _O(1)_ |  Medium | EPI, `quick sort`, bubble sort, sort, `amazon`,`fb`| OK* (2)
 228 | [Summary Ranges](https://leetcode.com/problems/summary-ranges/) | [Python](./leetcode_python/Array/summary-ranges.py), [Java](./leetcode_java/src/main/java/LeetCodeJava/Array/SummaryRanges.java) | _O(n)_ | _O(1)_ | Easy |check `# 163 Missing Ranges`, `basic`, array, `google`| OK*** (4) 

leetcode_java/src/main/java/LeetCodeJava/Array/RotateArray.java

@@ -0,0 +1,149 @@
+package LeetCodeJava.Array;
+
+// https://leetcode.com/problems/rotate-array/description/
+
+import java.util.ArrayList;
+import java.util.Deque;
+import java.util.LinkedList;
+import java.util.List;
+
+/**
+ * 189. Rotate Array
+ * Solved
+ * Medium
+ * Topics
+ * Companies
+ * Hint
+ * Given an integer array nums, rotate the array to the right by k steps, where k is non-negative.
+ *
+ *
+ *
+ * Example 1:
+ *
+ * Input: nums = [1,2,3,4,5,6,7], k = 3
+ * Output: [5,6,7,1,2,3,4]
+ * Explanation:
+ * rotate 1 steps to the right: [7,1,2,3,4,5,6]
+ * rotate 2 steps to the right: [6,7,1,2,3,4,5]
+ * rotate 3 steps to the right: [5,6,7,1,2,3,4]
+ * Example 2:
+ *
+ * Input: nums = [-1,-100,3,99], k = 2
+ * Output: [3,99,-1,-100]
+ * Explanation:
+ * rotate 1 steps to the right: [99,-1,-100,3]
+ * rotate 2 steps to the right: [3,99,-1,-100]
+ *
+ *
+ * Constraints:
+ *
+ * 1 <= nums.length <= 105
+ * -231 <= nums[i] <= 231 - 1
+ * 0 <= k <= 105
+ *
+ *
+ * Follow up:
+ *
+ * Try to come up with as many solutions as you can. There are at least three different ways to solve this problem.
+ * Could you do it in-place with O(1) extra space?
+ *
+ *
+ */
+public class RotateArray {
+
+    // V0
+    // IDEA: DEQEUE
+    public void rotate(int[] nums, int k) {
+        // edge
+        if (nums == null || nums.length == 0) {
+            return;
+        }
+
+        Deque<Integer> dq = new LinkedList<>();
+        for (int n : nums) {
+            dq.add(n);
+        }
+
+        int i = 0;
+        for (i = 0; i < k; i++) {
+            /**
+             *  NOTE !!! below
+             *
+             *   we get dequeue last element,
+             *   then append it to first idx
+             */
+            dq.addFirst(dq.pollLast());
+        }
+
+       // System.out.println(">>> dq = " + dq);
+
+        int j = 0;
+        while (!dq.isEmpty()) {
+            nums[j] = dq.pollFirst();
+            j += 1;
+        }
+    }
+
+    // V0-1
+    // IDEA: ARRAY OP (TLE)
+    public void rotate_0_1(int[] nums, int k) {
+        // edge
+        if (nums == null || nums.length == 0) {
+            return;
+        }
+
+        List<Integer> list = new ArrayList<>();
+        for (int n : nums) {
+            list.add(n);
+        }
+
+        int i = 0;
+        for (i = 0; i < k; i++) {
+            // int last = nums[nums.length - 1];
+            int last = list.get(list.size() - 1);
+            list.remove(list.size() - 1);
+            list.add(0, last);
+        }
+
+        for (int j = 0; j < list.size(); j++) {
+            nums[j] = list.get(j);
+        }
+    }
+
+    // V1
+    // IDEA: rotate ( `%` op)  (gpt)
+    public void rotate_1(int[] nums, int k) {
+        // Edge case
+        if (nums == null || nums.length == 0) {
+            return;
+        }
+
+        // Adjust k in case it's greater than the array length
+        k = k % nums.length;
+        if (k == 0) {
+            return;
+        }
+
+        // Reverse the entire array
+        reverse(nums, 0, nums.length - 1);
+
+        // Reverse the first k elements
+        reverse(nums, 0, k - 1);
+
+        // Reverse the remaining elements
+        reverse(nums, k, nums.length - 1);
+    }
+
+    private void reverse(int[] nums, int start, int end) {
+        while (start < end) {
+            int temp = nums[start];
+            nums[start] = nums[end];
+            nums[end] = temp;
+            start++;
+            end--;
+        }
+    }
+
+    // V2
+
+}

leetcode_java/src/main/java/dev/workspace8.java

@@ -9497,4 +9497,39 @@ public void merge(int[] nums1, int m, int[] nums2, int n) {
 
     }
 
+    // Lc 189
+    // 11.05 - 11.15 am
+    public void rotate(int[] nums, int k) {
+        // edge
+        if(nums == null || nums.length == 0){
+            return;
+        }
+
+        // ?? can use below ??
+        Deque<Integer> dq = new LinkedList<>();
+       // List<Integer> list = new ArrayList<>();
+        for(int n: nums){
+          //  list.add(n);
+            dq.add(n);
+        }
+
+        int i = 0;
+        for(i = 0; i < k; i++){
+           // int last = nums[nums.length - 1];
+//           int last = list.get(list.size()-1);
+//           list.remove(list.size()-1);
+//           list.add(0, last);
+
+          dq.addFirst(dq.pollLast()); // ???
+        }
+
+        System.out.println(">>> dq = " + dq);
+
+        int j = 0;
+        while(!dq.isEmpty()){
+            nums[j] = dq.pollFirst();
+            j += 1;
+        }
+    }
+
 }