diff --git a/.gitignore b/.gitignore
new file mode 100644
index 0000000..b13f319
--- /dev/null
+++ b/.gitignore
@@ -0,0 +1,6 @@
+target/
+*.class
+.idea/
+*.iml
+.vscode/
+.DS_Store
diff --git a/.mvn/jvm.config b/.mvn/jvm.config
new file mode 100644
index 0000000..e69de29
diff --git a/.mvn/maven.config b/.mvn/maven.config
new file mode 100644
index 0000000..e69de29
diff --git a/pom.xml b/pom.xml
new file mode 100644
index 0000000..568add7
--- /dev/null
+++ b/pom.xml
@@ -0,0 +1,60 @@
+<?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>com.mycompany.app</groupId>
+  <artifactId>my-app</artifactId>
+  <version>1.0-SNAPSHOT</version>
+  <packaging>jar</packaging>
+
+  <properties>
+    <maven.compiler.source>17</maven.compiler.source>
+    <maven.compiler.target>17</maven.compiler.target>
+    <project.build.sourceEncoding>UTF-8</project.build.sourceEncoding>
+  </properties>
+
+  <dependencies>
+    <dependency>
+      <groupId>org.junit.jupiter</groupId>
+      <artifactId>junit-jupiter</artifactId>
+      <version>5.10.2</version>
+      <scope>test</scope>
+    </dependency>
+  </dependencies>
+
+  <build>
+    <plugins>
+      <plugin>
+        <artifactId>maven-surefire-plugin</artifactId>
+        <version>3.3.0</version>
+        <configuration>
+          <forkCount>1</forkCount>
+          <testFailureIgnore>true</testFailureIgnore>
+        </configuration>
+      </plugin>
+
+      <plugin>
+        <groupId>org.jacoco</groupId>
+        <artifactId>jacoco-maven-plugin</artifactId>
+        <version>0.8.11</version>
+        <executions>
+          <execution>
+            <goals>
+              <goal>prepare-agent</goal>
+            </goals>
+          </execution>
+          <execution>
+            <id>report</id>
+            <phase>prepare-package</phase>
+            <goals>
+              <goal>report</goal>
+            </goals>
+          </execution>
+        </executions>
+      </plugin>
+    </plugins>
+  </build>
+</project>
\ No newline at end of file
diff --git a/src/main/java/com/mycompany/app/App.java b/src/main/java/com/mycompany/app/App.java
new file mode 100644
index 0000000..f67b506
--- /dev/null
+++ b/src/main/java/com/mycompany/app/App.java
@@ -0,0 +1,12 @@
+package com.mycompany.app;
+
+public class App
+{
+    public static void main(String[] args)
+    {
+        double val = Double.parseDouble("2.0");
+        Sqrt sqrt = new Sqrt(val);
+        double result = sqrt.calc();
+        System.out.println("Sqrt of " + val + " = " + result);
+    }
+}
\ No newline at end of file
diff --git a/src/main/java/com/mycompany/app/Sqrt.java b/src/main/java/com/mycompany/app/Sqrt.java
new file mode 100644
index 0000000..42c9eec
--- /dev/null
+++ b/src/main/java/com/mycompany/app/Sqrt.java
@@ -0,0 +1,34 @@
+package com.mycompany.app;
+
+public class Sqrt
+{
+    double delta = 0.00000001;
+    double arg;
+
+    public Sqrt(double arg) {
+        this.arg = arg;
+    }
+
+    public double average(double x, double y) {
+        return (x + y) / 2.0;
+    }
+
+    public boolean good(double guess, double x) {
+        return Math.abs(guess * guess - x) < delta;
+    }
+
+    public double improve(double guess, double x) {
+        return average(guess, x / guess);
+    }
+
+    public double iter(double guess, double x) {
+        if (good(guess, x))
+            return guess;
+        else
+            return iter(improve(guess, x), x);
+    }
+
+    public double calc() {
+        return iter(1.0, arg);
+    }
+}
\ No newline at end of file
diff --git a/src/test/java/com/mycompany/app/SqrtTest.java b/src/test/java/com/mycompany/app/SqrtTest.java
new file mode 100644
index 0000000..f1c7fb6
--- /dev/null
+++ b/src/test/java/com/mycompany/app/SqrtTest.java
@@ -0,0 +1,132 @@
+package com.mycompany.app;
+
+import org.junit.jupiter.api.Test;
+import org.junit.jupiter.api.BeforeEach;
+import static org.junit.jupiter.api.Assertions.*;
+
+public class SqrtTest {
+
+    private Sqrt sqrt4;
+    private Sqrt sqrt9;
+    private Sqrt sqrt2;
+
+    @BeforeEach
+    public void setUp() {
+        sqrt4 = new Sqrt(4.0);
+        sqrt9 = new Sqrt(9.0);
+        sqrt2 = new Sqrt(2.0);
+    }
+
+    /// --- Тесты метода calc() ---
+
+    @Test
+    public void testCalcPerfectSquare4() {
+        assertEquals(2.0, sqrt4.calc(), 1e-6,
+                "Квадратный корень из 4 должен быть 2.0");
+    }
+
+    @Test
+    public void testCalcPerfectSquare9() {
+        assertEquals(3.0, sqrt9.calc(), 1e-6,
+                "Квадратный корень из 9 должен быть 3.0");
+    }
+
+    @Test
+    public void testCalcPerfectSquare1() {
+        Sqrt sqrt1 = new Sqrt(1.0);
+        assertEquals(1.0, sqrt1.calc(), 1e-6,
+                "Квадратный корень из 1 должен быть 1.0");
+    }
+
+    @Test
+    public void testCalcIrrational() {
+        assertEquals(Math.sqrt(2.0), sqrt2.calc(), 1e-6,
+                "Квадратный корень из 2 должен совпадать с Math.sqrt(2)");
+    }
+
+    @Test
+    public void testCalcLargeNumber() {
+        Sqrt sqrtLarge = new Sqrt(1000000.0);
+        assertEquals(1000.0, sqrtLarge.calc(), 1e-4,
+                "Квадратный корень из 1000000 должен быть 1000.0");
+    }
+
+    @Test
+    public void testCalcSmallNumber() {
+        Sqrt sqrtSmall = new Sqrt(0.25);
+        assertEquals(0.5, sqrtSmall.calc(), 1e-6,
+                "Квадратный корень из 0.25 должен быть 0.5");
+    }
+
+    /// --- Тесты метода average() ---
+
+    @Test
+    public void testAverageOfTwoNumbers() {
+        assertEquals(3.0, sqrt4.average(2.0, 4.0), 1e-9,
+                "Среднее 2.0 и 4.0 должно быть 3.0");
+    }
+
+    @Test
+    public void testAverageSymmetry() {
+        assertEquals(sqrt4.average(1.0, 5.0), sqrt4.average(5.0, 1.0), 1e-9,
+                "average(a,b) должно быть равно average(b,a)");
+    }
+
+    @Test
+    public void testAverageEqualNumbers() {
+        assertEquals(7.0, sqrt4.average(7.0, 7.0), 1e-9,
+                "Среднее одинаковых чисел должно быть равно им самим");
+    }
+
+    /// --- Тесты метода good() ---
+
+    @Test
+    public void testGoodWhenGuessIsExact() {
+        assertTrue(sqrt4.good(2.0, 4.0),
+                "good(2.0, 4.0) должен вернуть true");
+    }
+
+    @Test
+    public void testGoodWhenGuessFar() {
+        assertFalse(sqrt4.good(10.0, 4.0),
+                "good(10.0, 4.0) должен вернуть false");
+    }
+
+    @Test
+    public void testGoodBoundaryNearDelta() {
+        assertTrue(sqrt9.good(3.0, 9.0),
+                "good(3.0, 9.0) должен вернуть true");
+    }
+
+    /// --- Тесты метода improve() ---
+
+    @Test
+    public void testImproveConvergesTowardsRoot() {
+        double improved = sqrt4.improve(1.0, 4.0);
+        assertEquals(2.5, improved, 1e-9,
+                "improve(1.0, 4.0) должен вернуть 2.5");
+    }
+
+    @Test
+    public void testImproveOnExactRoot() {
+        double improved = sqrt4.improve(2.0, 4.0);
+        assertEquals(2.0, improved, 1e-9,
+                "improve(2.0, 4.0) должен вернуть 2.0 (уже точный корень)");
+    }
+
+    /// --- Тесты метода iter() ---
+
+    @Test
+    public void testIterFromGoodGuess() {
+        double result = sqrt4.iter(2.0, 4.0);
+        assertEquals(2.0, result, 1e-6,
+                "iter(2.0, 4.0) должен вернуть 2.0");
+    }
+
+    @Test
+    public void testIterFromBadGuess() {
+        double result = sqrt9.iter(1.0, 9.0);
+        assertEquals(3.0, result, 1e-6,
+                "iter(1.0, 9.0) должен сойтись к 3.0");
+    }
+}
\ No newline at end of file