add 1089

Author: fishercoder1534

README.md

@@ -31,6 +31,7 @@ Your ideas/fixes/algorithms are more than welcome!
 |5083|[Occurrences After Bigram](https://leetcode.com/problems/occurrences-after-bigram/)|[Solution](../master/src/main/java/com/fishercoder/solutions/_5083.java) | O(n) | O(1) | |Easy||
 |1137|[N-th Tribonacci Number](https://leetcode.com/problems/n-th-tribonacci-number/)|[Solution](../master/src/main/java/com/fishercoder/solutions/_1137.java) | O(n) | O(n) | |Easy||
 |1122|[Relative Sort Array](https://leetcode.com/problems/relative-sort-array/)|[Solution](../master/src/main/java/com/fishercoder/solutions/_1122.java) | O(n) | O(n) | |Easy||
+|1089|[Duplicate Zeros](https://leetcode.com/problems/duplicate-zeros/)|[Solution](../master/src/main/java/com/fishercoder/solutions/_1089.java) | O(n^2) | O(1) | |Easy||
 |1071|[Greatest Common Divisor of Strings](https://leetcode.com/problems/greatest-common-divisor-of-strings/)|[Solution](../master/src/main/java/com/fishercoder/solutions/_1071.java) | O(m*n) | O(1) | |Easy||
 |1065|[Index Pairs of a String](https://leetcode.com/problems/index-pairs-of-a-string/)|[Solution](../master/src/main/java/com/fishercoder/solutions/_1065.java) | O(nlogn) | O(1) | |Medium||
 |1056|[Confusing Number](https://leetcode.com/problems/confusing-number/)|[Solution](../master/src/main/java/com/fishercoder/solutions/_1056.java) | O(n) | O(1) | |Easy||

src/main/java/com/fishercoder/solutions/_1089.java

@@ -0,0 +1,48 @@
+package com.fishercoder.solutions;
+
+/**
+ * 1089. Duplicate Zeros
+ *
+ * Given a fixed length array arr of integers, duplicate each occurrence of zero, shifting the remaining elements to the right.
+ *
+ * Note that elements beyond the length of the original array are not written.
+ *
+ * Do the above modifications to the input array in place, do not return anything from your function.
+ *
+ * Example 1:
+ * Input: [1,0,2,3,0,4,5,0]
+ * Output: null
+ * Explanation: After calling your function, the input array is modified to: [1,0,0,2,3,0,0,4]
+ *
+ * Example 2:
+ * Input: [1,2,3]
+ * Output: null
+ * Explanation: After calling your function, the input array is modified to: [1,2,3]
+ *
+ * Note:
+ *
+ * 1 <= arr.length <= 10000
+ * 0 <= arr[i] <= 9
+ * */
+public class _1089 {
+    public static class Solution1 {
+        public void duplicateZeros(int[] arr) {
+            for (int i = 0; i < arr.length - 1; i++) {
+                if (arr[i] == 0) {
+                    duplicateZeros(arr, i + 1);
+                    i++;
+                }
+            }
+        }
+
+        private void duplicateZeros(int[] arr, int zeroIndex) {
+            int tmp = arr[zeroIndex];
+            arr[zeroIndex] = 0;
+            for (int i = zeroIndex + 1; i < arr.length; i++) {
+                int next = arr[i];
+                arr[i] = tmp;
+                tmp = next;
+            }
+        }
+    }
+}

src/test/java/com/fishercoder/_1089Test.java

@@ -0,0 +1,32 @@
+package com.fishercoder;
+
+import com.fishercoder.solutions._1089;
+import org.junit.BeforeClass;
+import org.junit.Test;
+
+import static org.junit.Assert.assertArrayEquals;
+
+public class _1089Test {
+    private static _1089.Solution1 solution1;
+    private static int[] arr;
+
+    @BeforeClass
+    public static void setup() {
+        solution1 = new _1089.Solution1();
+    }
+
+    @Test
+    public void test1() {
+        arr = new int[]{1, 0, 2, 3, 0, 4, 5, 0};
+        solution1.duplicateZeros(arr);
+        assertArrayEquals(new int[]{1, 0, 0, 2, 3, 0, 0, 4}, arr);
+    }
+
+    @Test
+    public void test2() {
+        arr = new int[]{1, 2, 3};
+        solution1.duplicateZeros(arr);
+        assertArrayEquals(new int[]{1, 2, 3}, arr);
+    }
+
+}