add 2670

fishercoder1534 · fishercoder1534 · commit 588232bd8817 · 2023-05-07T07:53:50.000-07:00
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                                                                                                                                | Video                                                                         | Difficulty                       | Tag                  
 |------|----------------|------------------------------------------------------------------------------------------------------------------------------------------|-------------------------------------------------------------------------------|----------------------------------|-------------
+| 2670 |[Find the Distinct Difference Array](https://leetcode.com/problems/find-the-distinct-difference-array/)| [Java](../master/src/main/java/com/fishercoder/solutions/_2670.java)                                                                     |                                                                       | Easy                             |
 | 2596 |[Check Knight Tour Configuration](https://leetcode.com/problems/check-knight-tour-configuration/)| [Java](../master/src/main/java/com/fishercoder/solutions/_2596.java)                                                                     | [:tv:](https://youtu.be/OBht8NT_09c)                                                                      | Medium                           |
 | 2595 |[Number of Even and Odd Bits](https://leetcode.com/problems/number-of-even-and-odd-bits/)| [Java](../master/src/main/java/com/fishercoder/solutions/_2595.java)                                                                     |                                                                               | Easy                             |
 | 2586 |[Count the Number of Vowel Strings in Range](https://leetcode.com/problems/count-the-number-of-vowel-strings-in-range/)| [Java](../master/src/main/java/com/fishercoder/solutions/_2586.java)                                                                     |                                                                               | Easy                             |
diff --git a/src/main/java/com/fishercoder/solutions/_2670.java b/src/main/java/com/fishercoder/solutions/_2670.java
@@ -0,0 +1,30 @@
+package com.fishercoder.solutions;
+
+import java.util.HashMap;
+import java.util.Map;
+
+public class _2670 {
+    public static class Solution1 {
+        public int[] distinctDifferenceArray(int[] nums) {
+            Map<Integer, Integer> prefix = new HashMap<>();
+            prefix.put(nums[0], 1);
+            Map<Integer, Integer> suffix = new HashMap<>();
+            for (int i = 1; i < nums.length; i++) {
+                suffix.put(nums[i], suffix.getOrDefault(nums[i], 0) + 1);
+            }
+            int[] result = new int[nums.length];
+            for (int i = 0; i < nums.length; i++) {
+                result[i] = prefix.size() - suffix.size();
+                if (i + 1 < nums.length) {
+                    prefix.put(nums[i + 1], prefix.getOrDefault(nums[i + 1], 0) + 1);
+                    if (suffix.containsKey(nums[i + 1]) && suffix.get(nums[i + 1]) == 1) {
+                        suffix.remove(nums[i + 1]);
+                    } else {
+                        suffix.put(nums[i + 1], suffix.getOrDefault(nums[i + 1], 0) - 1);
+                    }
+                }
+            }
+            return result;
+        }
+    }
+}
diff --git a/src/test/java/com/fishercoder/_2670Test.java b/src/test/java/com/fishercoder/_2670Test.java
@@ -0,0 +1,22 @@
+package com.fishercoder;
+
+import com.fishercoder.solutions._2670;
+import org.junit.BeforeClass;
+import org.junit.Test;
+
+import static org.junit.Assert.assertArrayEquals;
+
+public class _2670Test {
+    private static _2670.Solution1 solution1;
+
+    @BeforeClass
+    public static void setup() {
+        solution1 = new _2670.Solution1();
+    }
+
+    @Test
+    public void test1() {
+        assertArrayEquals(new int[]{-2, -1, 0, 2, 3}, solution1.distinctDifferenceArray(new int[]{3, 2, 3, 4, 2}));
+    }
+
+}
