add 1281

fishercoder1534 · fishercoder1534 · commit 0c289e09a998 · 2019-12-08T14:55:09.000-08:00
diff --git a/README.md b/README.md
@@ -9,6 +9,7 @@ _If you like this project, please leave me a star._ &#9733;
 |  #  |      Title     |   Solutions   | Time          | Space         | Video  | Difficulty  | Tag                   
 |-----|----------------|---------------|---------------|---------------|--------|-------------|-------------
 |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/_1266.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||
 |1266|[Minimum Time Visiting All Points](https://leetcode.com/problems/minimum-time-visiting-all-points/)|[Solution](../master/src/main/java/com/fishercoder/solutions/_1266.java) |  |  | |Easy||
 |1260|[Shift 2D Grid](https://leetcode.com/problems/shift-2d-grid/)|[Solution](../master/src/main/java/com/fishercoder/solutions/_1260.java) |  |  | [:tv:](https://www.youtube.com/watch?v=9hBcARSiU0s)|Easy||
 |1252|[Cells with Odd Values in a Matrix](https://leetcode.com/problems/cells-with-odd-values-in-a-matrix/)|[Solution](../master/src/main/java/com/fishercoder/solutions/_1252.java) | O(m*n + k) | O(m*n) | |Easy||
diff --git a/src/main/java/com/fishercoder/solutions/_1281.java b/src/main/java/com/fishercoder/solutions/_1281.java
@@ -0,0 +1,41 @@
+package com.fishercoder.solutions;
+
+/**
+ * 1281. Subtract the Product and Sum of Digits of an Integer
+ *
+ * Given an integer number n, return the difference between the product of its digits and the sum of its digits.
+ *
+ * Example 1:
+ * Input: n = 234
+ * Output: 15
+ * Explanation:
+ * Product of digits = 2 * 3 * 4 = 24
+ * Sum of digits = 2 + 3 + 4 = 9
+ * Result = 24 - 9 = 15
+ *
+ * Example 2:
+ * Input: n = 4421
+ * Output: 21
+ * Explanation:
+ * Product of digits = 4 * 4 * 2 * 1 = 32
+ * Sum of digits = 4 + 4 + 2 + 1 = 11
+ * Result = 32 - 11 = 21
+ *
+ * Constraints:
+ * 1 <= n <= 10^5
+ * */
+public class _1281 {
+    public static class Solution1 {
+        public int subtractProductAndSum(int n) {
+            int sum = 0;
+            int product = 1;
+            while (n > 0) {
+                int digit = n % 10;
+                n /= 10;
+                sum += digit;
+                product *= digit;
+            }
+            return product - sum;
+        }
+    }
+}
diff --git a/src/test/java/com/fishercoder/_1281Test.java b/src/test/java/com/fishercoder/_1281Test.java
@@ -0,0 +1,22 @@
+package com.fishercoder;
+
+import com.fishercoder.solutions._1281;
+import org.junit.BeforeClass;
+import org.junit.Test;
+
+import static junit.framework.TestCase.assertEquals;
+
+public class _1281Test {
+    private static _1281.Solution1 solution1;
+
+    @BeforeClass
+    public static void setup() {
+        solution1 = new _1281.Solution1();
+    }
+
+    @Test
+    public void test1() {
+        assertEquals(15, solution1.subtractProductAndSum(234));
+    }
+
+}
