Count absolute distincts in sorted array

Chapter10/CountDistinctAbsoluteSortedArray/pom.xml

@@ -0,0 +1,14 @@
+<?xml version="1.0" encoding="UTF-8"?>
+<project xmlns="http://maven.apache.org/POM/4.0.0" xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance" xsi:schemaLocation="http://maven.apache.org/POM/4.0.0 http://maven.apache.org/xsd/maven-4.0.0.xsd">
+    <modelVersion>4.0.0</modelVersion>
+    <groupId>coding.challenge</groupId>
+    <artifactId>CountDistinctAbsoluteSortedArray</artifactId>
+    <version>1.0</version>
+    <packaging>jar</packaging>
+    <properties>
+        <project.build.sourceEncoding>UTF-8</project.build.sourceEncoding>
+        <maven.compiler.source>13</maven.compiler.source>
+        <maven.compiler.target>13</maven.compiler.target>
+    </properties>
+    <name>CountDistinctAbsoluteSortedArray</name>
+</project>

Chapter10/CountDistinctAbsoluteSortedArray/src/main/java/coding/challenge/Arrays.java

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+package coding.challenge;
+
+public final class Arrays {
+
+    private Arrays() {
+        throw new AssertionError("Cannot be instantiated");
+    }
+
+    public static int findAbsoluteDistinct(int[] m) {
+
+        if (m == null) {
+            return -1;
+        }
+
+        int count = m.length;
+
+        int left = 0;
+        int right = m.length - 1;
+
+        while (left < right) {
+
+            // remove duplicates elements from the left and right            
+            while (left < right && m[left] == m[left + 1]) {
+                count--;
+                left++;
+            }
+
+            while (right > left && m[right] == m[right - 1]) {
+                count--;
+                right--;
+            }
+
+            // only one element is left
+            if (left == right) {
+                break;
+            }
+
+            int sum = m[left] + m[right];
+
+            // decrease the distinct count if zero sum pair is encountered
+            if (sum == 0) {
+
+                count--;
+
+                left++;
+                right--;
+            } else if (sum < 0) {
+
+                left++;
+            } else {
+
+                right--;
+            }
+        }
+
+        return count;
+    }
+}

Chapter10/CountDistinctAbsoluteSortedArray/src/main/java/coding/challenge/Main.java

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+package coding.challenge;
+
+public class Main {
+
+    public static void main(String[] args) {
+
+        int[] m = {-3, -3, -2, -1, -1, -1, 0, 1, 1, 1, 2, 2, 3, 5, 6, 7, 7};
+
+        int result = Arrays.findAbsoluteDistinct(m);
+
+        System.out.println("Array: " + java.util.Arrays.toString(m));
+        System.out.print("The number of distinct absolute values is: "
+                + result);
+    }
+}