diff --git a/.DS_Store b/.DS_Store
new file mode 100644
index 0000000..c1efd8f
Binary files /dev/null and b/.DS_Store differ
diff --git a/.classpath b/.classpath
new file mode 100644
index 0000000..3f3893a
--- /dev/null
+++ b/.classpath
@@ -0,0 +1,6 @@
+<?xml version="1.0" encoding="UTF-8"?>
+<classpath>
+	<classpathentry kind="con" path="org.eclipse.jdt.launching.JRE_CONTAINER"/>
+	<classpathentry kind="src" path=""/>
+	<classpathentry kind="output" path=""/>
+</classpath>
diff --git a/.project b/.project
new file mode 100644
index 0000000..13c4477
--- /dev/null
+++ b/.project
@@ -0,0 +1,23 @@
+<?xml version="1.0" encoding="UTF-8"?>
+<projectDescription>
+	<name>2025-SS-welcome-test</name>
+	<comment></comment>
+	<projects>
+	</projects>
+	<buildSpec>
+		<buildCommand>
+			<name>org.eclipse.wst.validation.validationbuilder</name>
+			<arguments>
+			</arguments>
+		</buildCommand>
+		<buildCommand>
+			<name>org.eclipse.jdt.core.javabuilder</name>
+			<arguments>
+			</arguments>
+		</buildCommand>
+	</buildSpec>
+	<natures>
+		<nature>org.eclipse.jdt.core.javanature</nature>
+		<nature>org.eclipse.wst.jsdt.core.jsNature</nature>
+	</natures>
+</projectDescription>
diff --git a/.settings/.jsdtscope b/.settings/.jsdtscope
new file mode 100644
index 0000000..cca691f
--- /dev/null
+++ b/.settings/.jsdtscope
@@ -0,0 +1,7 @@
+<?xml version="1.0" encoding="UTF-8"?>
+<classpath>
+	<classpathentry kind="con" path="org.eclipse.wst.jsdt.launching.JRE_CONTAINER"/>
+	<classpathentry kind="con" path="org.eclipse.wst.jsdt.launching.baseBrowserLibrary"/>
+	<classpathentry kind="src" path=""/>
+	<classpathentry kind="output" path=""/>
+</classpath>
diff --git a/.settings/org.eclipse.wst.jsdt.ui.superType.container b/.settings/org.eclipse.wst.jsdt.ui.superType.container
new file mode 100644
index 0000000..49c8cd4
--- /dev/null
+++ b/.settings/org.eclipse.wst.jsdt.ui.superType.container
@@ -0,0 +1 @@
+org.eclipse.wst.jsdt.launching.JRE_CONTAINER
\ No newline at end of file
diff --git a/.settings/org.eclipse.wst.jsdt.ui.superType.name b/.settings/org.eclipse.wst.jsdt.ui.superType.name
new file mode 100644
index 0000000..11006e2
--- /dev/null
+++ b/.settings/org.eclipse.wst.jsdt.ui.superType.name
@@ -0,0 +1 @@
+Global
\ No newline at end of file
diff --git a/answer/.DS_Store b/answer/.DS_Store
new file mode 100644
index 0000000..572f171
Binary files /dev/null and b/answer/.DS_Store differ
diff --git a/java_test/.DS_Store b/java_test/.DS_Store
new file mode 100644
index 0000000..5008ddf
Binary files /dev/null and b/java_test/.DS_Store differ
diff --git a/java_test/.gitignore b/java_test/.gitignore
new file mode 100644
index 0000000..0441a2a
--- /dev/null
+++ b/java_test/.gitignore
@@ -0,0 +1,12 @@
+/Fan.class
+/a.class
+/b.class
+/c.class
+/d.class
+/e.class
+/f.class
+/g1.class
+/g2.class
+/Book.class
+/EBook.class
+/PrintedBook.class
diff --git a/java_test/a.java b/java_test/a.java
index 88363b2..2929300 100644
--- a/java_test/a.java
+++ b/java_test/a.java
@@ -1,10 +1,11 @@
 package java_test;
+import java.util.*;
 
 public class a {
     public static void main(String[] args) {
-
-        // 이 부분에 code를 작성해주세요!
-
+    	Scanner sc=new Scanner(System.in);
+    	String str=sc.nextLine();
+    	StringBuffer sb=new StringBuffer(str);
+    	System.out.println(sb.reverse());
     }
-
 }
\ No newline at end of file
diff --git a/java_test/b.java b/java_test/b.java
index 4225cb2..7276874 100644
--- a/java_test/b.java
+++ b/java_test/b.java
@@ -1,10 +1,18 @@
 package java_test;
+import java.util.*;
 
 public class b {
     public static void main(String[] args) {
-
-        // 이 부분에 code를 작성해주세요!
-
+    	Scanner sc=new Scanner(System.in);
+    	String str=sc.nextLine();
+    	String[] arr= {"a", "e", "i", "o", "u"};
+    	
+    	for(String s : arr) {
+    		if(str.contains(s)) {
+    			System.out.println("O");
+    			System.exit(0);
+    		}
+    	}
+    	System.out.println("X");
     }
-
 }
\ No newline at end of file
diff --git a/java_test/c.java b/java_test/c.java
index f9d081f..7c281aa 100644
--- a/java_test/c.java
+++ b/java_test/c.java
@@ -1,10 +1,16 @@
 package java_test;
+import java.util.*;
 
 public class c {
     public static void main(String[] args) {
-
-        // 이 부분에 code를 작성해주세요!
-
+    	Scanner sc=new Scanner(System.in);
+    	int num1=sc.nextInt();
+    	int num2=sc.nextInt();
+    	
+    	if(num1<14 && num2<155) {
+    		System.out.println("O");
+    	}else {
+    		System.out.println("X");
+    	}
     }
-
 }
\ No newline at end of file
diff --git a/java_test/d.java b/java_test/d.java
index 0137ce5..a083a74 100644
--- a/java_test/d.java
+++ b/java_test/d.java
@@ -1,10 +1,17 @@
 package java_test;
+import java.util.*;
 
 public class d {
     public static void main(String[] args) {
-
-        // 이 부분에 code를 작성해주세요!
-
+    	Scanner sc=new Scanner(System.in);
+    	while(true) {
+    		int num=sc.nextInt();
+    		if(num<=0) {
+    			System.out.println("X");
+    			break;
+    		}
+    		System.out.println(num*(num+1)/2);
+    		break;
+    	}
     }
-
 }
\ No newline at end of file
diff --git a/java_test/e.java b/java_test/e.java
index 6daa449..38d384b 100644
--- a/java_test/e.java
+++ b/java_test/e.java
@@ -1,10 +1,20 @@
 package java_test;
+import java.util.*;
 
 public class e {
     public static void main(String[] args) {
-
-        // 이 부분에 code를 작성해주세요!
-
+    	Scanner sc=new Scanner(System.in);
+    	int num1=sc.nextInt();
+    	int num2=sc.nextInt();
+    	
+    	if(num2==4 || num2==6 || num2==9 || num2==11) {
+    		System.out.println("30");
+    	}else if(num1%4==0 && (num1%100!=0 || num1%400==0) && num2==2) {
+    		System.out.println("29");
+    	}else if(num2==2) {
+    		System.out.println("28");
+    	}else {
+    		System.out.println("31");
+    	}
     }
-
 }
\ No newline at end of file
diff --git a/java_test/f.java b/java_test/f.java
index 1249954..baa3cbc 100644
--- a/java_test/f.java
+++ b/java_test/f.java
@@ -1,12 +1,20 @@
 package java_test;
-
-// 이부분에 class 선언 해도 괜찮습니다
+import java.util.*;
 
 public class f {
     public static void main(String[] args) {
-
-        // 이 부분에 code를 작성해주세요!
-
+    	Scanner sc=new Scanner(System.in);
+    	int num=sc.nextInt(), p=1;
+    	
+    	for(int i=1, j=num-1; i>0 ;i+=p*2, j-=p) {
+    		if(i>num*2) {
+    			p*=-1;
+    			i+=p*2; j-=p;
+    			continue;
+    		}
+    		for(int k=0; k<j ;k++) System.out.print(" ");
+    		for(int k=0; k<i ;k++) System.out.print("*");
+    		System.out.println();
+    	}
     }
-
 }
diff --git a/java_test/g1.java b/java_test/g1.java
index 3d071e0..66d75e5 100644
--- a/java_test/g1.java
+++ b/java_test/g1.java
@@ -1,12 +1,45 @@
-package java_test;
-
-// 이부분에 class 선언 해도 괜찮습니다
-
-public class g1 {
-    public static void main(String[] args) {
-
-        // 이 부분에 code를 작성해주세요!
-
-    }
-
-}
\ No newline at end of file
+package java_test;
+import java.util.*;
+
+class Fan implements Comparable<Fan> {
+	private String model;
+	private int price;
+	
+	Fan(String model, int price) {
+		this.model=model;
+		this.price=price;
+	}
+	
+	String getModel() { return model; }
+	int getPrice() { return price; }
+	
+	@Override
+	public int compareTo(Fan o) {
+		if(this.price>o.price) {
+			return 1;
+		}else if(this.price<o.price) {
+			return -1;
+		}else {
+			return 0;
+		}
+	}
+}
+
+public class g1 {
+    public static void main(String[] args) {
+    	Scanner sc=new Scanner(System.in);
+    	ArrayList<Fan> fan=new ArrayList<>();
+    	
+    	for(int i=0; i<3 ;i++) {
+    		if(i!=0) sc.nextLine();
+    		String model=sc.nextLine();
+    		int price=sc.nextInt();
+    		fan.add(new Fan(model, price));
+    	}
+    	
+    	Collections.sort(fan);
+    	System.out.println(fan.get(0).getModel());
+    	
+    }
+}
+
diff --git a/java_test/g2.java b/java_test/g2.java
index 5f214d7..591805f 100644
--- a/java_test/g2.java
+++ b/java_test/g2.java
@@ -1,12 +1,94 @@
-package java_test;
-
-// 이부분에 class 선언 해도 괜찮습니다
-
-public class g2 {
-    public static void main(String[] args) {
-
-        // 이 부분에 code를 작성해주세요!
-
-    }
-
-}
\ No newline at end of file
+package java_test;
+import java.util.*;
+
+abstract class Book implements Comparable<Book> {
+	String title;
+	int price;
+	double rating;
+	
+	@Override
+	public int compareTo(Book o) {
+		if(this.rating>o.rating) {
+			return -1;
+		}else if(this.rating<o.rating) {
+			return 1;
+		}else {
+			return 0;
+		}
+	}
+	
+	abstract int getExtra();
+}
+
+class EBook extends Book {
+	int fileSize;
+	
+	EBook(String title, int price, double rating, int fileSize) {
+		this.title=title;
+		this.price=price;
+		this.rating=rating;
+		this.fileSize=fileSize;
+	}
+	
+	int getExtra() { return fileSize; }
+}
+
+class PrintedBook extends Book {
+	int pageCount;
+	
+	PrintedBook(String title, int price, double rating, int pageCount) {
+		this.title=title;
+		this.price=price;
+		this.rating=rating;
+		this.pageCount=pageCount;
+	}
+	
+	int getExtra() { return pageCount; }
+}
+
+public class g2 {
+    public static void main(String[] args) {
+    	ArrayList<Book> arr=new ArrayList<>();
+    	Scanner sc=new Scanner(System.in);
+    	boolean isFirst=true;
+    	for(int i=0; i<3 ;i++) {
+    		if(!isFirst) sc.nextLine();
+    		String genre=sc.nextLine();
+    		if(!genre.equals("EBook") && !genre.equals("PrintedBook")) {
+    			System.out.println("Invalid book type. Please enter 'EBook' or 'PrintedBook'.");
+    			isFirst=true;
+    			i--;
+    			continue;
+    		}
+    		String title=sc.nextLine();
+    		try {
+    			int price=sc.nextInt();
+    			double rating=sc.nextDouble();
+    			int extra=sc.nextInt();
+    			
+    			if(genre.equals("EBook")) {
+    				arr.add(new EBook(title, price, rating, extra));
+    			}else {
+    				arr.add(new PrintedBook(title, price, rating, extra));
+    			}
+    		}catch(Exception e) {
+    			System.out.println("잘못된 입력입니다. 처음부터 다시 입력하세요.");
+    			i--;
+    		}
+    		isFirst=false;
+    	}
+    	
+    	Collections.sort(arr);
+    	Book book=arr.get(0);
+    	System.out.println("Highest rated book information:");
+    	System.out.println("Title: "+book.title);
+    	System.out.println("Price: "+book.price);
+    	System.out.println("Rating: "+book.rating);
+    	if(book.getClass().getName().contains("Printed")) {
+    		System.out.println("Page Count: "+book.getExtra());
+    	}else {
+    		System.out.println("File Size: "+book.getExtra());
+    	}
+    }
+}
+