Added task 768.

Author: javadev

src/main/java/g0701_0800/s0768_max_chunks_to_make_sorted_ii/Solution.java

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+package g0701_0800.s0768_max_chunks_to_make_sorted_ii;
+
+// #Hard #Array #Sorting #Greedy #Stack #Monotonic_Stack
+
+public class Solution {
+    public int maxChunksToSorted(int[] arr) {
+        int n = arr.length;
+        int[] lmax = new int[n];
+        int[] rmin = new int[n + 1];
+        lmax[0] = arr[0];
+        for (int i = 1; i < n; i++) {
+            lmax[i] = Math.max(lmax[i - 1], arr[i]);
+        }
+        rmin[n] = Integer.MAX_VALUE;
+        for (int i = n - 1; i >= 0; i--) {
+            rmin[i] = Math.min(rmin[i + 1], arr[i]);
+        }
+        int chunks = 0;
+        for (int i = 0; i < n; i++) {
+            if (lmax[i] <= rmin[i + 1]) {
+                chunks++;
+            }
+        }
+        return chunks;
+    }
+}

src/main/java/g0701_0800/s0768_max_chunks_to_make_sorted_ii/readme.md

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+768\. Max Chunks To Make Sorted II
+
+Hard
+
+You are given an integer array `arr`.
+
+We split `arr` into some number of **chunks** (i.e., partitions), and individually sort each chunk. After concatenating them, the result should equal the sorted array.
+
+Return _the largest number of chunks we can make to sort the array_.
+
+**Example 1:**
+
+**Input:** arr = [5,4,3,2,1]
+
+**Output:** 1
+
+**Explanation:**
+
+    Splitting into two or more chunks will not return the required result.
+    For example, splitting into [5, 4], [3, 2, 1] will result in [4, 5, 1, 2, 3], which isn't sorted. 
+
+**Example 2:**
+
+**Input:** arr = [2,1,3,4,4]
+
+**Output:** 4
+
+**Explanation:**
+
+    We can split into two chunks, such as [2, 1], [3, 4, 4].
+    However, splitting into [2, 1], [3], [4], [4] is the highest number of chunks possible. 
+
+**Constraints:**
+
+*   `1 <= arr.length <= 2000`
+*   <code>0 <= arr[i] <= 10<sup>8</sup></code>

src/test/java/g0701_0800/s0768_max_chunks_to_make_sorted_ii/SolutionTest.java

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+package g0701_0800.s0768_max_chunks_to_make_sorted_ii;
+
+import static org.hamcrest.CoreMatchers.equalTo;
+import static org.hamcrest.MatcherAssert.assertThat;
+
+import org.junit.jupiter.api.Test;
+
+class SolutionTest {
+    @Test
+    void maxChunksToSorted() {
+        assertThat(new Solution().maxChunksToSorted(new int[] {5, 4, 3, 2, 1}), equalTo(1));
+    }
+
+    @Test
+    void maxChunksToSorted2() {
+        assertThat(new Solution().maxChunksToSorted(new int[] {2, 1, 3, 4, 4}), equalTo(4));
+    }
+}