add 1472

Author: fishercoder1534

README.md

@@ -276,6 +276,7 @@ _If you like this project, please leave me a star._ ★
 |1476|[Subrectangle Queries](https://leetcode.com/problems/subrectangle-queries/)|[Solution](../master/src/main/java/com/fishercoder/solutions/_1476.java) | |Medium|Array|
 |1475|[Final Prices With a Special Discount in a Shop](https://leetcode.com/problems/final-prices-with-a-special-discount-in-a-shop/)|[Solution](../master/src/main/java/com/fishercoder/solutions/_1475.java) | |Easy|Array|
 |1474|[Delete N Nodes After M Nodes of a Linked List](https://leetcode.com/problems/delete-n-nodes-after-m-nodes-of-a-linked-list/)|[Solution](../master/src/main/java/com/fishercoder/solutions/_1474.java) | |Easy|LinkedList|
+|1472|[Design Browser History](https://leetcode.com/problems/design-browser-history/)|[Solution](../master/src/main/java/com/fishercoder/solutions/_1472.java) | |Medium|Array, Design|
 |1471|[The k Strongest Values in an Array](https://leetcode.com/problems/the-k-strongest-values-in-an-array/)|[Solution](../master/src/main/java/com/fishercoder/solutions/_1471.java) | |Medium|Array, Sort|
 |1470|[Shuffle the Array](https://leetcode.com/problems/shuffle-the-array/)|[Solution](../master/src/main/java/com/fishercoder/solutions/_1470.java), [C++](../master/cpp/_1470.cpp) | |Easy|Array|
 |1469|[Find All The Lonely Nodes](https://leetcode.com/problems/find-all-the-lonely-nodes/)|[Solution](../master/src/main/java/com/fishercoder/solutions/_1469.java) | |Easy|Tree, DFS|

src/main/java/com/fishercoder/solutions/_1472.java

@@ -0,0 +1,43 @@
+package com.fishercoder.solutions;
+
+import java.util.ArrayList;
+import java.util.List;
+
+public class _1472 {
+    public static class Solution1 {
+        public static class BrowserHistory {
+
+            int curr;
+            List<String> history;
+
+            public BrowserHistory(String homepage) {
+                history = new ArrayList<>();
+                history.add(homepage);
+                curr = 0;
+            }
+
+            public void visit(String url) {
+                curr++;
+                history = history.subList(0, curr);
+                history.add(url);
+            }
+
+            public String back(int steps) {
+                curr -= steps;
+                if (curr < 0) {
+                    curr = 0;
+                }
+                return history.get(curr);
+            }
+
+            public String forward(int steps) {
+                curr += steps;
+                if (history.size() <= curr) {
+                    curr = history.size() - 1;
+                }
+                return history.get(curr);
+            }
+        }
+
+    }
+}

src/test/java/com/fishercoder/_1472Test.java

@@ -0,0 +1,26 @@
+package com.fishercoder;
+
+import com.fishercoder.solutions._1472;
+import org.junit.Test;
+
+import static org.junit.Assert.assertEquals;
+
+public class _1472Test {
+    private static _1472.Solution1.BrowserHistory browserHistory;
+
+    @Test
+    public void test1() {
+        browserHistory = new _1472.Solution1.BrowserHistory("leetcode.com");
+        browserHistory.visit("google.com");
+        browserHistory.visit("facebook.com");
+        browserHistory.visit("youtube.com");
+        assertEquals("facebook.com", browserHistory.back(1));
+        assertEquals("google.com", browserHistory.back(1));
+        assertEquals("facebook.com", browserHistory.forward(1));
+        browserHistory.visit("linkedin.com");
+        assertEquals("linkedin.com", browserHistory.forward(2));
+        assertEquals("google.com", browserHistory.back(2));
+        assertEquals("leetcode.com", browserHistory.back(7));
+    }
+
+}