diff --git "a/src/main/java/Step1_\355\225\231\354\212\265\355\205\214\354\212\244\355\212\270/CharMethods.java" "b/src/main/java/Step1_\355\225\231\354\212\265\355\205\214\354\212\244\355\212\270/CharMethods.java"
new file mode 100644
index 0000000..61e7c80
--- /dev/null
+++ "b/src/main/java/Step1_\355\225\231\354\212\265\355\205\214\354\212\244\355\212\270/CharMethods.java"
@@ -0,0 +1,7 @@
+package Step1_학습테스트;
+
+public class CharMethods {
+    public char charAt(String string, int index) {
+        return string.charAt(index);
+    }
+}
diff --git "a/src/main/java/Step1_\355\225\231\354\212\265\355\205\214\354\212\244\355\212\270/SetMethods.java" "b/src/main/java/Step1_\355\225\231\354\212\265\355\205\214\354\212\244\355\212\270/SetMethods.java"
new file mode 100644
index 0000000..3449768
--- /dev/null
+++ "b/src/main/java/Step1_\355\225\231\354\212\265\355\205\214\354\212\244\355\212\270/SetMethods.java"
@@ -0,0 +1,10 @@
+package Step1_학습테스트;
+
+import java.util.Set;
+
+public class SetMethods {
+    public int getSize(Set<Integer> set) {
+        return set.size();
+    }
+
+}
diff --git "a/src/main/java/Step1_\355\225\231\354\212\265\355\205\214\354\212\244\355\212\270/StringMethods.java" "b/src/main/java/Step1_\355\225\231\354\212\265\355\205\214\354\212\244\355\212\270/StringMethods.java"
new file mode 100644
index 0000000..5f6335e
--- /dev/null
+++ "b/src/main/java/Step1_\355\225\231\354\212\265\355\205\214\354\212\244\355\212\270/StringMethods.java"
@@ -0,0 +1,11 @@
+package Step1_학습테스트;
+
+public class StringMethods {
+    public String[] splitStrings(String string) {
+        return string.split("");
+    }
+
+    public static String subString(String string, int a, int b) {
+        return string.substring(a,b);
+    }
+}
diff --git a/src/main/java/Step2_Calculator/ArithmeticOperation.java b/src/main/java/Step2_Calculator/ArithmeticOperation.java
new file mode 100644
index 0000000..f0a53a9
--- /dev/null
+++ b/src/main/java/Step2_Calculator/ArithmeticOperation.java
@@ -0,0 +1,41 @@
+package Step2_Calculator;
+
+public class  ArithmeticOperation {
+
+    public static int arithmeticOperation(int acc, int curr, String arithmeticOperator) {
+
+        if(arithmeticOperator.equals("+")){
+            return sum(acc, curr);
+        }
+
+        if(arithmeticOperator.equals("-")){
+            return subtract(acc, curr);
+        }
+
+        if(arithmeticOperator.equals("/")){
+            return divide(acc, curr);
+        }
+
+        if(arithmeticOperator.equals("*")){
+            return multiply(acc, curr);
+        }
+
+        return acc;
+    }
+
+    private static int sum(int acc, int curr) {
+        return acc + curr;
+    }
+
+    private static int divide(int acc, int curr) {
+        return acc / curr;
+    }
+
+    private static int multiply(int acc, int curr) {
+        return acc * curr;
+    }
+
+    private static int subtract(int acc, int curr) {
+        return acc - curr;
+    }
+}
diff --git a/src/main/java/Step2_Calculator/Calculator.java b/src/main/java/Step2_Calculator/Calculator.java
new file mode 100644
index 0000000..7d3ed78
--- /dev/null
+++ b/src/main/java/Step2_Calculator/Calculator.java
@@ -0,0 +1,17 @@
+package Step2_Calculator;
+
+public class Calculator {
+    private int accumulator;
+
+    public int calculate(String s) {
+        InputErrorHandler.checkCalculatorIllegalArgument(s);
+        String[] arithmetics = InputExtactor.extractCalculatorInputs(s);
+        
+        accumulator = Integer.parseInt(arithmetics[0]);
+
+        for(int i = 1; i< arithmetics.length; i += 2) {
+              accumulator = ArithmeticOperation.arithmeticOperation(accumulator, Integer.parseInt(arithmetics[i+1]), arithmetics[i]);
+        }
+        return accumulator;
+    }
+}
diff --git a/src/main/java/Step2_Calculator/CalculatorApp.java b/src/main/java/Step2_Calculator/CalculatorApp.java
new file mode 100644
index 0000000..3875721
--- /dev/null
+++ b/src/main/java/Step2_Calculator/CalculatorApp.java
@@ -0,0 +1,11 @@
+package Step2_Calculator;
+
+public class CalculatorApp {
+    public static void main(String[] args) {
+        InputView.startCalculator();
+        String input = InputView.inputArithmeticOperations();
+        Calculator calculator = new Calculator();
+        int result = calculator.calculate(input);
+        OutputView.showOutput(result);
+    }
+}
diff --git a/src/main/java/Step2_Calculator/InputErrorHandler.java b/src/main/java/Step2_Calculator/InputErrorHandler.java
new file mode 100644
index 0000000..bed5bb2
--- /dev/null
+++ b/src/main/java/Step2_Calculator/InputErrorHandler.java
@@ -0,0 +1,17 @@
+package Step2_Calculator;
+
+public class InputErrorHandler {
+    public static void checkCalculatorIllegalArgument(String s){
+        String numbersToSingleLength = s.replaceAll("-?\\d+", "1");
+        String noSpace = numbersToSingleLength.replaceAll(" ", "");
+        if(numbersToSingleLength.length() != noSpace.length()*2-1) {
+            throw new IllegalArgumentException("Wrong input Format! Must be (number) (arithmetic Operator) (number) ... so on with no null inputs");
+        }
+
+        if(!s.matches("[\\d+*/\\-]+")){
+            System.out.println("asdasdasd");
+            throw new IllegalArgumentException("Wrong inputs!!!");
+        }
+
+    }
+}
diff --git a/src/main/java/Step2_Calculator/InputExtactor.java b/src/main/java/Step2_Calculator/InputExtactor.java
new file mode 100644
index 0000000..6e137a1
--- /dev/null
+++ b/src/main/java/Step2_Calculator/InputExtactor.java
@@ -0,0 +1,7 @@
+package Step2_Calculator;
+
+public class InputExtactor {
+    public static String[] extractCalculatorInputs(String s) {
+        return s.split(" ");
+    }
+}
diff --git a/src/main/java/Step2_Calculator/InputView.java b/src/main/java/Step2_Calculator/InputView.java
new file mode 100644
index 0000000..e81272d
--- /dev/null
+++ b/src/main/java/Step2_Calculator/InputView.java
@@ -0,0 +1,16 @@
+package Step2_Calculator;
+
+import java.util.Scanner;
+
+public class InputView {
+    private static Scanner scanner;
+
+    public static void startCalculator(){
+        System.out.print("Input Arithmetic Operations : ");
+    }
+    public static String inputArithmeticOperations() {
+        scanner = new Scanner(System.in);
+        return scanner.nextLine();
+    }
+
+}
diff --git a/src/main/java/Step2_Calculator/OutputView.java b/src/main/java/Step2_Calculator/OutputView.java
new file mode 100644
index 0000000..747a357
--- /dev/null
+++ b/src/main/java/Step2_Calculator/OutputView.java
@@ -0,0 +1,9 @@
+package Step2_Calculator;
+
+public class OutputView {
+
+    public static void showOutput(int result) {
+        System.out.println("Result :" + result);
+    }
+
+}
diff --git a/src/main/java/empty.txt b/src/main/java/empty.txt
index e69de29..24c6c86 100644
--- a/src/main/java/empty.txt
+++ b/src/main/java/empty.txt
@@ -0,0 +1 @@
+ㄷㄱㅀㄴㄷㄹ
\ No newline at end of file
diff --git a/src/main/java/step3_racing_car/Car.java b/src/main/java/step3_racing_car/Car.java
new file mode 100644
index 0000000..25661d5
--- /dev/null
+++ b/src/main/java/step3_racing_car/Car.java
@@ -0,0 +1,16 @@
+package step3_racing_car;
+
+import java.util.Random;
+
+public class Car {
+
+    public static int move() {
+        return movable() ? 1 : 0;
+    }
+
+    public static boolean movable() {
+        int randomNumber = RandomGenerator.generateNumber(10);
+        return randomNumber < 5 ? false : true;
+    }
+
+}
diff --git a/src/main/java/step3_racing_car/CarList.java b/src/main/java/step3_racing_car/CarList.java
new file mode 100644
index 0000000..5a69303
--- /dev/null
+++ b/src/main/java/step3_racing_car/CarList.java
@@ -0,0 +1,19 @@
+package step3_racing_car;
+
+import java.util.stream.Collectors;
+import java.util.stream.IntStream;
+import java.util.stream.Stream;
+
+public class CarList {
+
+    public static String[] getNames(String carNames) {
+        return carNames.split(",");
+    }
+    
+    public static String[] getIndexNames(String[] carListNames, int[] winnersIndex) {
+        return IntStream.range(0, carListNames.length)
+                .filter(i -> IntStream.of(winnersIndex).anyMatch(x-> x== i))
+                .mapToObj(i -> carListNames[i])
+                .toArray(String[]::new);
+    }
+}
\ No newline at end of file
diff --git a/src/main/java/step3_racing_car/InputView.java b/src/main/java/step3_racing_car/InputView.java
new file mode 100644
index 0000000..8304b86
--- /dev/null
+++ b/src/main/java/step3_racing_car/InputView.java
@@ -0,0 +1,24 @@
+package step3_racing_car;
+
+import java.util.Scanner;
+
+public class InputView {
+    private static Scanner scanner;
+    public static int carAmount() {
+        System.out.println("자동차 대수는 몇 대 인가요?");
+        scanner = new Scanner(System.in);
+        return scanner.nextInt();
+    }
+
+    public static String carNames() {
+        System.out.println("경주할 자동차 이름을 입력하세요(이름은 쉼표(,)를 기준으로 구분).");
+        scanner = new Scanner(System.in);
+        return scanner.nextLine();
+    }
+
+    public static int loopCount() {
+        System.out.println("시도할 회수는 몇 회 인가요?");
+        scanner = new Scanner(System.in);
+        return scanner.nextInt();
+    }
+}
diff --git a/src/main/java/step3_racing_car/README.md b/src/main/java/step3_racing_car/README.md
new file mode 100644
index 0000000..ac9c6cb
--- /dev/null
+++ b/src/main/java/step3_racing_car/README.md
@@ -0,0 +1,26 @@
+기능을 구현하기 전에 README.md 파일에 구현할 기능 목록을 정리해 추가한다
+
+
+App
+- RacingGame -> app controller
+    1. inputView 자동차 대수는 몇 대 인가요?  
+                  a  
+                  시도할 회수는 몇 회 인가요?  
+                  b  
+                  출력(실행)
+    2. input값 car 도메인에 전달.               
+
+Domain
+- car
+    1. move(a,b)
+    2. randomMove()
+- carList
+    1. getNames() 
+    2. getIndexNames()
+- RaceCalculator
+    1. calculateWinner
+    2. calculateFurthestPosition
+    
+UI
+- InputView -> input 넣는 scanner
+- ResultView -> 출력할 System.out의 문구들
\ No newline at end of file
diff --git a/src/main/java/step3_racing_car/RaceCalculator.java b/src/main/java/step3_racing_car/RaceCalculator.java
new file mode 100644
index 0000000..a87153a
--- /dev/null
+++ b/src/main/java/step3_racing_car/RaceCalculator.java
@@ -0,0 +1,20 @@
+package step3_racing_car;
+
+import java.util.Arrays;
+import java.util.stream.IntStream;
+
+public class RaceCalculator {
+
+    public static int[] calculateWinner(int[] carPositions){
+        int furthestPosition = calculateFurthestPosition(carPositions);
+        return IntStream.range(0, carPositions.length)
+                .filter(i -> furthestPosition == carPositions[i])
+                .mapToObj(i->i)
+                .mapToInt(x -> x)
+                .toArray();
+    }
+
+    public static int calculateFurthestPosition(int[] carPositions) {
+       return Arrays.stream(carPositions).max().getAsInt();
+    }
+}
diff --git a/src/main/java/step3_racing_car/RacingGame.java b/src/main/java/step3_racing_car/RacingGame.java
new file mode 100644
index 0000000..e68616b
--- /dev/null
+++ b/src/main/java/step3_racing_car/RacingGame.java
@@ -0,0 +1,38 @@
+package step3_racing_car;
+
+public class RacingGame {
+    private static int[] carPositions;
+    private static int time;
+
+    public RacingGame(int[] carPositions, int time) {
+        this.carPositions = carPositions;
+        this.time = time;
+    }
+
+    public static void main(String[] args) {
+        String carNames = InputView.carNames();
+        String[] carListNames = CarList.getNames(carNames);
+        carPositions = new int[carListNames.length];
+        time = InputView.loopCount();
+        move(carListNames);
+        int[] winnersIndex = RaceCalculator.calculateWinner(carPositions);
+        String[] winnerList = CarList.getIndexNames(carListNames, winnersIndex);
+        ResultView.showWinner(winnerList);
+    }
+
+    public static int[] move(String[] carListNames) {
+        ResultView.startMove();
+        for(int j =0; j < time; j ++ ) {
+            changePosition();
+            ResultView.carPositions(carPositions,carListNames);
+        }
+        return carPositions;
+    }
+
+    public static void changePosition() {
+        for (int i = 0; i < carPositions.length; i++) {
+            carPositions[i] += Car.move();
+        }
+    }
+
+}
\ No newline at end of file
diff --git a/src/main/java/step3_racing_car/RandomGenerator.java b/src/main/java/step3_racing_car/RandomGenerator.java
new file mode 100644
index 0000000..d8e97e1
--- /dev/null
+++ b/src/main/java/step3_racing_car/RandomGenerator.java
@@ -0,0 +1,12 @@
+package step3_racing_car;
+
+import java.util.Random;
+
+public class RandomGenerator {
+    private static Random generator;
+
+    public static int generateNumber(int max) {
+        generator = new Random();
+        return generator.nextInt(max);
+    }
+}
diff --git a/src/main/java/step3_racing_car/ResultView.java b/src/main/java/step3_racing_car/ResultView.java
new file mode 100644
index 0000000..9e8f0f4
--- /dev/null
+++ b/src/main/java/step3_racing_car/ResultView.java
@@ -0,0 +1,31 @@
+package step3_racing_car;
+
+public class ResultView {
+    public static void carPositions(int[] carPositions, String[] carListNames) {
+        System.out.println();
+        for(int i = 0; i< carListNames.length; i ++) {
+            System.out.print(carListNames[i] + " : ");
+            printPosition(carPositions[i]);
+            System.out.println();
+        }
+    }
+
+    public static void printPosition(int position) {
+        for(int i = 0; i <= position; i ++) {
+            System.out.print("-");
+        }
+    }
+
+    public static void startMove() {
+        System.out.println("실행 결과");
+    }
+
+    public static void showWinner(String[] winnerList) {
+        for(String winner : winnerList) {
+            System.out.print(winner + " ");
+        }
+        System.out.println("(이)가 최종 우승했습니다.");
+    }
+
+
+}
diff --git "a/src/test/java/Step1_\355\225\231\354\212\265\355\205\214\354\212\244\355\212\270/CharMethodsTest.java" "b/src/test/java/Step1_\355\225\231\354\212\265\355\205\214\354\212\244\355\212\270/CharMethodsTest.java"
new file mode 100644
index 0000000..34b5431
--- /dev/null
+++ "b/src/test/java/Step1_\355\225\231\354\212\265\355\205\214\354\212\244\355\212\270/CharMethodsTest.java"
@@ -0,0 +1,51 @@
+package Step1_학습테스트;
+
+import Step1_학습테스트.CharMethods;
+import org.junit.jupiter.api.BeforeEach;
+import org.junit.jupiter.api.DisplayName;
+import org.junit.jupiter.api.Test;
+import org.junit.jupiter.params.ParameterizedTest;
+import org.junit.jupiter.params.provider.CsvSource;
+
+import static org.assertj.core.api.Assertions.*;
+import static org.assertj.core.api.Assertions.assertThatExceptionOfType;
+
+@DisplayName("Char Methods 테스트")
+public class CharMethodsTest {
+    private CharMethods charMethods;
+    @BeforeEach
+    void setUp() {
+        charMethods = new CharMethods();
+    }
+
+    @DisplayName("charAt 테스트")
+    @ParameterizedTest
+    @CsvSource(value = {"abc:0:a", "abc:1:b", "abc:2:c"}, delimiter = ':')
+    public void charIOTest(String string,int index, char expected) {
+        assertThat(charMethods.charAt(string, index)).isEqualTo(expected);
+    }
+
+    @DisplayName("charAt Error Index out of bound 테스트")
+    @Test
+    public void charErrorTest() {
+
+        assertThatThrownBy(() -> {
+            charMethods.charAt("abc", 3);
+        }).isInstanceOf(IndexOutOfBoundsException.class)
+                .hasMessageContaining("String index out of range: 3");
+
+//        Throwable thrown = catchThrowable(() -> { throw new Exception("String index out of range: 3"); });
+//        assertThat(thrown).isInstanceOf(Exception.class) .hasMessageContaining("String index out of range: 3");
+
+        assertThatExceptionOfType(IndexOutOfBoundsException.class).isThrownBy(() -> charMethods.charAt("abc", 3))
+                .withMessage("String index out of range: 3")
+                .withMessageContaining("String")
+                .withNoCause();
+
+//        assertThatExceptionOfType(IndexOutOfBoundsException.class).isThrownBy(() -> { throw new IndexOutOfBoundsException("NO!"); })
+//                .withMessage("NO!")
+//                .withMessageContaining("NO")
+//                .withNoCause();
+
+    }
+}
diff --git "a/src/test/java/Step1_\355\225\231\354\212\265\355\205\214\354\212\244\355\212\270/SetMethodsTest.java" "b/src/test/java/Step1_\355\225\231\354\212\265\355\205\214\354\212\244\355\212\270/SetMethodsTest.java"
new file mode 100644
index 0000000..30deb2b
--- /dev/null
+++ "b/src/test/java/Step1_\355\225\231\354\212\265\355\205\214\354\212\244\355\212\270/SetMethodsTest.java"
@@ -0,0 +1,61 @@
+package Step1_학습테스트;
+
+import Step1_학습테스트.SetMethods;
+import org.junit.jupiter.api.BeforeEach;
+import org.junit.jupiter.api.DisplayName;
+import org.junit.jupiter.api.Test;
+import org.junit.jupiter.params.ParameterizedTest;
+import org.junit.jupiter.params.provider.CsvSource;
+import org.junit.jupiter.params.provider.ValueSource;
+import static org.junit.jupiter.api.Assertions.assertTrue;
+
+
+import java.util.HashSet;
+import java.util.Set;
+
+import static org.assertj.core.api.Assertions.*;
+
+@DisplayName("set Method Test")
+public class SetMethodsTest {
+    private Set<Integer> numbers;
+    private SetMethods setMethods;
+    @BeforeEach
+    void setUp() {
+        setMethods = new SetMethods();
+        numbers = new HashSet<>();
+        numbers.add(1);
+        numbers.add(1);
+        numbers.add(2);
+        numbers.add(3);
+    }
+
+    @DisplayName("set 사이즈 테스트")
+    @Test
+    public void setSizeTest() {
+        int setSize = setMethods.getSize(numbers);
+        assertThat(setSize).isEqualTo(3);
+    }
+
+    @DisplayName("set 내용물 확인 테스트")
+    @ParameterizedTest
+    @ValueSource(ints = {1,1,2,3})
+    public void setContainsTest(int number) {
+        assertThat(numbers.contains(number)).isTrue();
+    }
+
+//    @Test
+//    public void setThrowErrorTest() {
+//        assertThat(numbers.contains(true)).isEqualTo(false);
+//        assertThat(numbers.contains(4)).isEqualTo(false);
+//        assertThat(numbers.contains(5)).isEqualTo(false);
+//    }
+
+    @DisplayName("set 입력 출력 테스트")
+    @ParameterizedTest
+    @CsvSource(value = {"1:true", "2:true", "3:true", "4:false", "5:false" }, delimiter = ':')
+    public void setIOTest(int input, boolean expected) {
+        assertThat(numbers.contains(input)).isEqualTo(expected);
+
+    }
+
+}
diff --git "a/src/test/java/Step1_\355\225\231\354\212\265\355\205\214\354\212\244\355\212\270/StringMethodsTest.java" "b/src/test/java/Step1_\355\225\231\354\212\265\355\205\214\354\212\244\355\212\270/StringMethodsTest.java"
new file mode 100644
index 0000000..724a4d8
--- /dev/null
+++ "b/src/test/java/Step1_\355\225\231\354\212\265\355\205\214\354\212\244\355\212\270/StringMethodsTest.java"
@@ -0,0 +1,44 @@
+package Step1_학습테스트;
+
+import Step1_학습테스트.StringMethods;
+import org.junit.jupiter.api.BeforeEach;
+import org.junit.jupiter.api.DisplayName;
+import org.junit.jupiter.api.Test;
+
+import static org.assertj.core.api.Assertions.*;
+
+@DisplayName("String Method 테스트")
+public class StringMethodsTest {
+    private StringMethods stringMethods;
+
+    @BeforeEach
+    void setUp() {
+        stringMethods = new StringMethods();
+    }
+
+    @DisplayName("String split 테스트")
+    @Test
+    public void splitStringTest() {
+        String[] splittedString = stringMethods.splitStrings("12");
+        assertThat(splittedString).contains("1","2");
+        assertThat(splittedString).containsExactly("1","2");
+        assertThat(splittedString).isEqualTo(new String[]{"1","2"});
+
+        String[] splittedString1 = stringMethods.splitStrings("1");
+        assertThat(splittedString1).isEqualTo(new String[]{"1"});
+        assertThat(splittedString1).contains("1");
+        assertThat(splittedString1).containsExactly("1");
+
+    }
+
+    @DisplayName("String subString 테스트")
+    @Test
+    public void subStringTest() {
+        String modifiedString = stringMethods.subString("(1,2)", 1,4);
+        assertThat(modifiedString).isEqualTo("1,2");
+        assertThat(modifiedString).doesNotContain("(");
+        assertThat(modifiedString).doesNotContain(")");
+    }
+}
+
+
diff --git a/src/test/java/Step2_Calculator/CalculatorTest.java b/src/test/java/Step2_Calculator/CalculatorTest.java
new file mode 100644
index 0000000..cf02e0a
--- /dev/null
+++ b/src/test/java/Step2_Calculator/CalculatorTest.java
@@ -0,0 +1,67 @@
+package Step2_Calculator;
+
+import Step2_Calculator.Calculator;
+import org.junit.jupiter.api.BeforeEach;
+import org.junit.jupiter.api.DisplayName;
+import org.junit.jupiter.api.Test;
+import org.junit.jupiter.params.ParameterizedTest;
+import org.junit.jupiter.params.provider.CsvSource;
+import static org.assertj.core.api.Assertions.assertThatIllegalArgumentException;
+
+import static org.assertj.core.api.Assertions.*;
+
+public class CalculatorTest {
+    private Calculator calculator;
+
+    @BeforeEach
+    void setUp() {
+        calculator = new Calculator();
+    }
+
+    @DisplayName("test calculator")
+    @ParameterizedTest
+    @CsvSource(value = {"2 + 3 * 4 / 2:10", "1:1", "0 * 10 * 11 + 3: 3"}, delimiter = ':')
+    public void calculatorTestArithmeticOperations(String arithmetic, int result) {
+        assertThat(calculator.calculate(arithmetic)).isEqualTo(result);
+    }
+
+    @DisplayName("null input")
+    @Test
+    public void calculatorTestWithNull() {
+        assertThatIllegalArgumentException().isThrownBy(() -> {
+           calculator.calculate("null");
+        });
+    }
+
+    @DisplayName("wrong input")
+    @Test
+    public void calculatorTestWithWrongInput() {
+        assertThatIllegalArgumentException().isThrownBy(() -> {
+             calculator.calculate("!");
+        });
+    }
+
+    @DisplayName("wrong format")
+    @Test
+    public void calculatorTestWithWrongFormat() {
+        assertThatIllegalArgumentException().isThrownBy(() -> {
+             calculator.calculate("4 + a");
+        });
+    }
+
+    @DisplayName("space inputs")
+    @Test
+    public void calculatorTestWithSpaceInputs() {
+        assertThatIllegalArgumentException().isThrownBy(() -> {
+            calculator.calculate("4 + 1 *  2");
+        });
+    }
+
+    @DisplayName("negative inputs")
+    @Test
+    public void calculatorTestWithNegativeInputs() {
+        assertThat(calculator.calculate("-4 - 1 * 2")).isEqualTo(-10);
+    }
+
+
+}
diff --git a/src/test/java/step3_racing_car/CarListTest.java b/src/test/java/step3_racing_car/CarListTest.java
new file mode 100644
index 0000000..77b63cc
--- /dev/null
+++ b/src/test/java/step3_racing_car/CarListTest.java
@@ -0,0 +1,24 @@
+package step3_racing_car;
+
+import org.junit.jupiter.api.BeforeEach;
+import org.junit.jupiter.api.DisplayName;
+import org.junit.jupiter.api.Test;
+
+import static org.assertj.core.api.Assertions.assertThat;
+import static org.junit.jupiter.api.Assertions.assertTrue;
+
+public class CarListTest {
+    @Test
+    public void getNamesTest(){
+        CarList carList = new CarList();
+        assertThat( carList.getNames("a,b,c")).isEqualTo(new String[] {"a","b","c"});
+    }
+    @Test
+    public void getIndexNamesTest(){
+        CarList carList = new CarList();
+        carList.getIndexNames(new String[] {"a","b"}, new int[] {1});
+        assertThat(carList.getIndexNames(new String[] {"a","b", "c"}, new int[] {1})).isEqualTo(new String[] {"b"});
+    }
+
+
+}
diff --git a/src/test/java/step3_racing_car/CarTest.java b/src/test/java/step3_racing_car/CarTest.java
new file mode 100644
index 0000000..9bdaa2d
--- /dev/null
+++ b/src/test/java/step3_racing_car/CarTest.java
@@ -0,0 +1,31 @@
+package step3_racing_car;
+
+import org.junit.jupiter.api.BeforeEach;
+import org.junit.jupiter.api.DisplayName;
+import org.junit.jupiter.api.Test;
+
+import static org.assertj.core.api.Assertions.assertThat;
+import static org.junit.jupiter.api.Assertions.assertTrue;
+
+public class CarTest {
+    private Car car;
+
+    @BeforeEach
+    void setUp() {
+        car = new Car();
+    }
+
+    @DisplayName("randomMoveable tests if movable returns true or false")
+    @Test
+    public void randomMovableTest() {
+        assertThat(car.movable()).isEqualTo(true||false);
+    }
+
+    @DisplayName("randomMove returns 0 or 1")
+    @Test
+    public void randomMoveTest() {
+        assertTrue(car.move() == 1 || car.move() == 0);
+    }
+
+
+}
diff --git a/src/test/java/step3_racing_car/RaceCalculatorTest.java b/src/test/java/step3_racing_car/RaceCalculatorTest.java
new file mode 100644
index 0000000..a5a4e0c
--- /dev/null
+++ b/src/test/java/step3_racing_car/RaceCalculatorTest.java
@@ -0,0 +1,23 @@
+package step3_racing_car;
+
+import org.junit.jupiter.api.Test;
+
+import static org.assertj.core.api.Assertions.assertThat;
+import static org.junit.jupiter.api.Assertions.assertTrue;
+
+
+public class RaceCalculatorTest {
+
+    @Test
+    public void calculateWinnerTest(){
+        RaceCalculator raceCalculator = new RaceCalculator();
+        assertThat(raceCalculator.calculateWinner(new int[] {4,5,6,6})).isEqualTo(new int[] {2,3});
+    }
+
+    @Test
+    public void calculateFurthestPosition() {
+        RaceCalculator raceCalculator = new RaceCalculator();
+        assertThat(raceCalculator.calculateFurthestPosition(new int[] {4,5,6,6})).isEqualTo(6);
+    }
+
+}
diff --git a/src/test/java/step3_racing_car/RacingGameTest.java b/src/test/java/step3_racing_car/RacingGameTest.java
new file mode 100644
index 0000000..fff429e
--- /dev/null
+++ b/src/test/java/step3_racing_car/RacingGameTest.java
@@ -0,0 +1,25 @@
+package step3_racing_car;
+
+import org.junit.jupiter.api.BeforeEach;
+import org.junit.jupiter.api.DisplayName;
+import org.junit.jupiter.api.Test;
+
+import static org.assertj.core.api.Assertions.assertThat;
+import static org.junit.jupiter.api.Assertions.assertTrue;
+
+
+public class RacingGameTest {
+    private RacingGame racingGame;
+
+    @BeforeEach
+    void setUp() {
+        racingGame = new RacingGame(new int[] {0,0,0,0,0}, 5);
+    }
+
+    @DisplayName("if moved")
+    @Test
+    public void moveTest() {
+        assertTrue(racingGame.move(new String[] {}).length == 5);
+    }
+
+}
diff --git a/src/test/java/step3_racing_car/RandomGeneratorTest.java b/src/test/java/step3_racing_car/RandomGeneratorTest.java
new file mode 100644
index 0000000..9d9a463
--- /dev/null
+++ b/src/test/java/step3_racing_car/RandomGeneratorTest.java
@@ -0,0 +1,22 @@
+package step3_racing_car;
+
+
+import org.junit.jupiter.api.BeforeEach;
+import org.junit.jupiter.api.Test;
+import static org.junit.jupiter.api.Assertions.assertTrue;
+
+public class RandomGeneratorTest {
+    private RandomGenerator randomGenerator;
+
+    @BeforeEach
+    void setUp() {
+        randomGenerator = new RandomGenerator();
+    }
+
+    @Test
+    public void randomMoveTest() {
+        int generatedRandomIntNumber = randomGenerator.generateNumber(10);
+        assertTrue(generatedRandomIntNumber <= 10);
+    }
+
+}
diff --git a/test b/test
new file mode 100644
index 0000000..028e2d8
--- /dev/null
+++ b/test
@@ -0,0 +1 @@
+test pull request
\ No newline at end of file