diff --git a/src/practice01/Prob1.java b/src/practice01/Prob1.java
index c038781..801f561 100644
--- a/src/practice01/Prob1.java
+++ b/src/practice01/Prob1.java
@@ -5,8 +5,15 @@
 public class Prob1 {
 	public static void main(String[] args) {
 		Scanner scanner = new Scanner( System.in );
-		
+		System.out.print("수를 입력하시오 : ");
+		int n = scanner.nextInt();
+		if(n%3 == 0) {
+			System.out.println("3의 배수입니다.");
+		}else {
+			System.out.println("3의 배수가 아닙니다.");
+		}
 		
 		scanner.close();
+		//
 	}
 }
diff --git a/src/practice01/Prob2.java b/src/practice01/Prob2.java
index 32d40f0..9636e0c 100644
--- a/src/practice01/Prob2.java
+++ b/src/practice01/Prob2.java
@@ -2,5 +2,12 @@
 
 public class Prob2 {
 	public static void main(String[] args) {
+		
+		for(int i = 1; i < 10;i++) {
+		for(int j = i ; j < i+10; j++) {
+			System.out.print(j+" ");
+		}
+		System.out.println();
+		}
 	}
 }
diff --git a/src/practice01/Prob3.java b/src/practice01/Prob3.java
index 3b7ab3c..ebd649f 100644
--- a/src/practice01/Prob3.java
+++ b/src/practice01/Prob3.java
@@ -1,7 +1,34 @@
 package practice01;
-
+import java.util.Scanner;
 public class Prob3 {
 	
 	public static void main(String[] args) {
+		Scanner s = new Scanner( System.in );
+		int sum1 = 0;
+		int sum2 = 0;
+		int n ;
+		while(true) {
+			sum1 = 0;
+			sum2 = 0;
+		System.out.print("숫자를 입력하세요: ");
+		n = s.nextInt();
+		for(int i = 0 ; i<=n ; i++) {
+			if(i%2 == 0) {
+				sum1 += i; 
+			}else if(i%2 == 1) {
+				sum2 += i;
+			}
+		}
+		
+		System.out.print("결과 값 : ");
+		if(n%2 == 0) {
+			System.out.println(sum1);	
+		}else if(n%2 == 1) {
+			System.out.println(sum2);	
+		}
+		
+		}
+		
+		
 	}
 }
diff --git a/src/practice01/Prob4.java b/src/practice01/Prob4.java
index 7d38c33..4dbe392 100644
--- a/src/practice01/Prob4.java
+++ b/src/practice01/Prob4.java
@@ -1,9 +1,21 @@
 package practice01;
 
+import java.util.Scanner;
 
 public class Prob4 {
 
 	public static void main(String[] args) {
+		
+		Scanner s = new Scanner(System.in);
+		
+		System.out.print("문자열을 입력하세요. : ");
+		String str = s.nextLine();
+		for(int i = 0 ; i < str.length() ; i++) {
+		for(int j = 0 ; j < i+1 ; j++) {
+			System.out.print(str.charAt(j));
+		}
+		System.out.println();
+		}
 	}
 
 }
diff --git a/src/practice01/Prob5.java b/src/practice01/Prob5.java
index d8d08ad..fad41b8 100644
--- a/src/practice01/Prob5.java
+++ b/src/practice01/Prob5.java
@@ -3,5 +3,19 @@
 public class Prob5 {
 
 	public static void main(String[] args) {
+		String str = new String();
+		for(int i = 1 ; i <= 1000 ; i++) {
+			str = String.valueOf(i);
+			
+			if(str.contains("3")||str.contains("6")||str.contains("9")) {
+				System.out.print(i+" ");
+			for(int j=0; j < str.length() ; j++) {
+				if(str.charAt(j) == '3' || str.charAt(j) == '6' || str.charAt(j) == '9') {
+					System.out.print("짝");
+				}
+			}
+			System.out.println();
+			}
+		}
 	}
 }