2022-10-06 update: added "Online Stock Span" (#126)

Author: fartem

README.md

@@ -590,6 +590,7 @@ Profile on LeetCode: [fartem](https://leetcode.com/fartem/).
 | 889. Construct Binary Tree from Preorder and Postorder Traversal                    | [Link](https://leetcode.com/problems/construct-binary-tree-from-preorder-and-postorder-traversal/)                   | [Link](./src/main/java/com/smlnskgmail/jaman/leetcodejava/medium/ConstructBinaryTreeFromPreorderAndPostorderTraversal.java)            |
 | 890. Find and Replace Pattern                                                       | [Link](https://leetcode.com/problems/find-and-replace-pattern/)                                                      | [Link](./src/main/java/com/smlnskgmail/jaman/leetcodejava/medium/FindAndReplacePattern.java)                                           |
 | 894. All Possible Full Binary Trees                                                 | [Link](https://leetcode.com/problems/all-possible-full-binary-trees/)                                                | [Link](./src/main/java/com/smlnskgmail/jaman/leetcodejava/medium/AllPossibleFullBinaryTrees.java)                                      |
+| 901. Online Stock Span                                                              | [Link](https://leetcode.com/problems/online-stock-span/)                                                             | [Link](./src/main/java/com/smlnskgmail/jaman/leetcodejava/medium/OnlineStockSpan.java)                                                 |
 | 910. Smallest Range II                                                              | [Link](https://leetcode.com/problems/smallest-range-ii/)                                                             | [Link](./src/main/java/com/smlnskgmail/jaman/leetcodejava/medium/SmallestRangeII.java)                                                 |
 | 912. Sort an Array                                                                  | [Link](https://leetcode.com/problems/sort-an-array/)                                                                 | [Link](./src/main/java/com/smlnskgmail/jaman/leetcodejava/medium/SortAnArray.java)                                                     |
 | 916. Word Subsets                                                                   | [Link](https://leetcode.com/problems/word-subsets/)                                                                  | [Link](./src/main/java/com/smlnskgmail/jaman/leetcodejava/medium/WordSubsets.java)                                                     |

src/main/java/com/smlnskgmail/jaman/leetcodejava/medium/OnlineStockSpan.java

@@ -0,0 +1,19 @@
+package com.smlnskgmail.jaman.leetcodejava.medium;
+
+import java.util.Stack;
+
+// https://leetcode.com/problems/online-stock-span/
+public class OnlineStockSpan {
+
+    private final Stack<int[]> stack = new Stack<>();
+
+    public int next(int price) {
+        int result = 1;
+        while (!stack.isEmpty() && stack.peek()[0] <= price) {
+            result += stack.pop()[1];
+        }
+        stack.push(new int[]{price, result});
+        return result;
+    }
+
+}

src/test/java/com/smlnskgmail/jaman/leetcodejava/medium/OnlineStockSpanTest.java

@@ -0,0 +1,21 @@
+package com.smlnskgmail.jaman.leetcodejava.medium;
+
+import org.junit.Test;
+
+import static org.junit.Assert.assertEquals;
+
+public class OnlineStockSpanTest {
+
+    @Test
+    public void defaultTest() {
+        var onlineStockSpan = new OnlineStockSpan();
+        assertEquals(1, onlineStockSpan.next(100));
+        assertEquals(1, onlineStockSpan.next(80));
+        assertEquals(1, onlineStockSpan.next(60));
+        assertEquals(2, onlineStockSpan.next(70));
+        assertEquals(1, onlineStockSpan.next(60));
+        assertEquals(4, onlineStockSpan.next(75));
+        assertEquals(6, onlineStockSpan.next(85));
+    }
+
+}