add 1290

fishercoder1534 · fishercoder1534 · commit 0efd32df3b85 · 2019-12-15T07:04:29.000-08:00
diff --git a/README.md b/README.md
@@ -8,6 +8,7 @@ _If you like this project, please leave me a star._ &#9733;
 
 |  #  |      Title     |   Solutions   | Time          | Space         | Video  | Difficulty  | Tag                   
 |-----|----------------|---------------|---------------|---------------|--------|-------------|-------------
+|1290|[Convert Binary Number in a Linked List to Integer](https://leetcode.com/problems/convert-binary-number-in-a-linked-list-to-integer/)|[Solution](../master/src/main/java/com/fishercoder/solutions/_1290.java) |  |  | |Easy||
 |1287|[Element Appearing More Than 25% In Sorted Array](https://leetcode.com/problems/element-appearing-more-than-25-in-sorted-array/)|[Solution](../master/src/main/java/com/fishercoder/solutions/_1287.java) |  |  | |Easy||
 |1282|[Group the People Given the Group Size They Belong To](https://leetcode.com/problems/group-the-people-given-the-group-size-they-belong-to/)|[Solution](../master/src/main/java/com/fishercoder/solutions/_1282.java) |  |  | |Medium||
 |1281|[Subtract the Product and Sum of Digits of an Integer](https://leetcode.com/problems/subtract-the-product-and-sum-of-digits-of-an-integer/)|[Solution](../master/src/main/java/com/fishercoder/solutions/_1281.java) |  |  | |Easy||
diff --git a/src/main/java/com/fishercoder/solutions/_1290.java b/src/main/java/com/fishercoder/solutions/_1290.java
@@ -0,0 +1,52 @@
+package com.fishercoder.solutions;
+
+import com.fishercoder.common.classes.ListNode;
+
+/**
+ * 1290. Convert Binary Number in a Linked List to Integer
+ *
+ * Given head which is a reference node to a singly-linked list.
+ * The value of each node in the linked list is either 0 or 1.
+ * The linked list holds the binary representation of a number.
+ *
+ * Return the decimal value of the number in the linked list.
+ *
+ * Example 1:
+ * Input: head = [1,0,1]
+ * Output: 5
+ * Explanation: (101) in base 2 = (5) in base 10
+ *
+ * Example 2:
+ * Input: head = [0]
+ * Output: 0
+ *
+ * Example 3:
+ * Input: head = [1]
+ * Output: 1
+ *
+ * Example 4:
+ * Input: head = [1,0,0,1,0,0,1,1,1,0,0,0,0,0,0]
+ * Output: 18880
+ *
+ * Example 5:
+ * Input: head = [0,0]
+ * Output: 0
+ *
+ * Constraints:
+ *
+ * The Linked List is not empty.
+ * Number of nodes will not exceed 30.
+ * Each node's value is either 0 or 1.
+ * */
+public class _1290 {
+    public static class Solution1 {
+        public int getDecimalValue(ListNode head) {
+            StringBuilder sb = new StringBuilder();
+            while (head != null) {
+                sb.append(head.val);
+                head = head.next;
+            }
+            return Integer.parseInt(sb.toString(), 2);
+        }
+    }
+}
diff --git a/src/test/java/com/fishercoder/_1290Test.java b/src/test/java/com/fishercoder/_1290Test.java
@@ -0,0 +1,27 @@
+package com.fishercoder;
+
+import com.fishercoder.common.classes.ListNode;
+import com.fishercoder.solutions._1290;
+import org.junit.BeforeClass;
+import org.junit.Test;
+
+import java.util.Arrays;
+
+import static junit.framework.TestCase.assertEquals;
+
+public class _1290Test {
+    private static _1290.Solution1 solution1;
+    private static ListNode head;
+
+    @BeforeClass
+    public static void setup() {
+        solution1 = new _1290.Solution1();
+    }
+
+    @Test
+    public void test1() {
+        head = ListNode.createSinglyLinkedList(Arrays.asList(1, 0, 1));
+        assertEquals(5, solution1.getDecimalValue(head));
+    }
+
+}
