diff --git a/src/main/java/gpacalc/Application.java b/src/main/java/gpacalc/Application.java
index 57e79e1..39e0536 100644
--- a/src/main/java/gpacalc/Application.java
+++ b/src/main/java/gpacalc/Application.java
@@ -1,7 +1,62 @@
 package gpacalc;
 
+import static camp.nextstep.edu.missionutils.Console.readLine;
+
+//import gpacalc.Subject; ...
+
+import java.util.ArrayList;
+
 public class Application {
     public static void main(String[] args) {
         //TODO: 구현
+
+        String input_M;
+        String input_G;
+        ArrayList<Subject> subjects_M = new ArrayList<>();
+        ArrayList<Subject> subjects_G = new ArrayList<>();
+        Operator op = new Operator();
+
+        System.out.println("전공 과목명과 이수학점, 평점을 입력해주세요(예시: 프로그래밍언어론-3-A+,소프트웨어공학-3-B+):");
+        input_M = readLine();
+
+        String[] input_Ms = input_M.split(",");
+
+        for (String inputM : input_Ms) {
+            String[] info = inputM.split("-");
+            Subject sub = new Subject(info[0], info[1], info[2]);
+            subjects_M.add(sub);
+        }
+
+        System.out.println("교양 과목명과 이수학점, 평점을 입력해주세요(예시: 선형대수학-3-C0,인간관계와자기성장-3-P):");
+        input_G = readLine();
+        String[] input_Gs = input_G.split(",");
+        for (String inputG : input_Gs) {
+            String[] info = inputG.split("-");
+            Subject sub = new Subject(info[0], info[1], info[2]);
+                subjects_G.add(sub);
+        }
+
+        op.checkGradeError(subjects_M, subjects_G);
+        op.checkCreditError(subjects_M, subjects_G);
+
+
+
+        System.out.println("<과목 목록>");
+        op.listOfSubjects(subjects_M, subjects_G);
+
+
+        System.out.println("\n<취득학점>");
+        System.out.print(op.getCredit(subjects_M, subjects_G));
+        System.out.println("학점");
+
+        System.out.println("\n<평점평균>");
+        System.out.print(Math.round(op.averageAllScore(subjects_M, subjects_G) * 100) / 100.0);
+        System.out.println(" / 4.5");
+
+        System.out.println("\n<전공 평점평균>");
+        System.out.print(op.averageMajorScore(subjects_M, subjects_G));
+        System.out.println(" / 4.5");
+
+
     }
 }
diff --git a/src/main/java/gpacalc/Operator.java b/src/main/java/gpacalc/Operator.java
new file mode 100644
index 0000000..33f1064
--- /dev/null
+++ b/src/main/java/gpacalc/Operator.java
@@ -0,0 +1,199 @@
+package gpacalc;
+
+import java.util.ArrayList;
+
+public class Operator {
+
+    public int getCredit_except_F_NP(ArrayList<Subject> subjects_M, ArrayList<Subject> subjects_G){
+        int credit = 0;
+        for(int i = 0; i<subjects_M.size(); i++){
+            if(!(subjects_M.get(i).getGrade().equals("P")) && !(subjects_M.get(i).getGrade().equals("NP"))){
+            credit += Integer.parseInt(subjects_M.get(i).getCredit());
+            }
+
+        }
+        for(int i = 0; i<subjects_G.size(); i++){
+            if(!(subjects_G.get(i).getGrade().equals("P")) && !(subjects_G.get(i).getGrade().equals("NP"))){
+                credit += Integer.parseInt(subjects_G.get(i).getCredit());
+            }
+        }
+
+        return credit;
+    }
+
+    public int getCredit(ArrayList<Subject> subjects_M, ArrayList<Subject> subjects_G){
+        int credit = 0;
+        for(int i = 0; i<subjects_M.size(); i++){
+            if(!(subjects_M.get(i).getGrade().equals("F")) && !(subjects_M.get(i).getGrade().equals("NP"))){
+                credit += Integer.parseInt(subjects_M.get(i).getCredit());
+            }
+
+        }
+        for(int i = 0; i<subjects_G.size(); i++){
+            if(!(subjects_G.get(i).getGrade().equals("F")) && !(subjects_G.get(i).getGrade().equals("NP"))){
+                credit += Integer.parseInt(subjects_G.get(i).getCredit());
+            }
+        }
+
+        return credit;
+    }
+
+
+    public float averageAllScore(ArrayList<Subject> subjects_M, ArrayList<Subject> subjects_G) {
+        float allAverage = 0;
+        float sgwAverage = 0.F;
+        for (int i = 0; i < subjects_M.size(); i++) {
+            if (!(subjects_M.get(i).getGrade().equals("P")) && !(subjects_M.get(i).getGrade().equals("NP"))) {
+                if (subjects_M.get(i).getGrade().equals("A+")) {
+                    sgwAverage += 4.5F * Integer.parseInt(subjects_M.get(i).getCredit());
+                } else if (subjects_M.get(i).getGrade().equals("A0")) {
+                    sgwAverage += 4.0F * Integer.parseInt(subjects_M.get(i).getCredit());
+                } else if (subjects_M.get(i).getGrade().equals("B+")) {
+                    sgwAverage += 3.5F * Integer.parseInt(subjects_M.get(i).getCredit());
+                } else if (subjects_M.get(i).getGrade().equals("B0")) {
+                    sgwAverage += 3.0F * Integer.parseInt(subjects_M.get(i).getCredit());
+                } else if (subjects_M.get(i).getGrade().equals("C+")) {
+                    sgwAverage += 2.5F * Integer.parseInt(subjects_M.get(i).getCredit());
+                } else if (subjects_M.get(i).getGrade().equals("C0")) {
+                    sgwAverage += 2.0F * Integer.parseInt(subjects_M.get(i).getCredit());
+                } else if (subjects_M.get(i).getGrade().equals("D+")) {
+                    sgwAverage += 1.5F * Integer.parseInt(subjects_M.get(i).getCredit());
+                } else if (subjects_M.get(i).getGrade().equals("D0")) {
+                    sgwAverage += 1.0F * Integer.parseInt(subjects_M.get(i).getCredit());
+                } else if (subjects_M.get(i).getGrade().equals("F")) {
+                    sgwAverage += 0.F * Integer.parseInt(subjects_M.get(i).getCredit());
+                }
+            }
+        }
+
+
+        for (int i = 0; i < subjects_G.size(); i++) {
+            if (!(subjects_G.get(i).getGrade().equals("P")) && !(subjects_G.get(i).getGrade().equals("NP"))) {
+                if (subjects_G.get(i).getGrade().equals("A+")) {
+                    sgwAverage += 4.5F * Integer.parseInt(subjects_G.get(i).getCredit());
+                } else if (subjects_G.get(i).getGrade().equals("A0")) {
+                    sgwAverage += 4.0F * Integer.parseInt(subjects_G.get(i).getCredit());
+                } else if (subjects_G.get(i).getGrade().equals("B+")) {
+                    sgwAverage += 3.5F * Integer.parseInt(subjects_G.get(i).getCredit());
+                } else if (subjects_G.get(i).getGrade().equals("B0")) {
+                    sgwAverage += 3.0F * Integer.parseInt(subjects_G.get(i).getCredit());
+                } else if (subjects_G.get(i).getGrade().equals("C+")) {
+                    sgwAverage += 2.5F * Integer.parseInt(subjects_G.get(i).getCredit());
+                } else if (subjects_G.get(i).getGrade().equals("C0")) {
+                    sgwAverage += 2.0F * Integer.parseInt(subjects_G.get(i).getCredit());
+                } else if (subjects_G.get(i).getGrade().equals("D+")) {
+                    sgwAverage += 1.5F * Integer.parseInt(subjects_G.get(i).getCredit());
+                } else if (subjects_G.get(i).getGrade().equals("D0")) {
+                    sgwAverage += 1.0F * Integer.parseInt(subjects_G.get(i).getCredit());
+                } else if (subjects_G.get(i).getGrade().equals("F")) {
+                    sgwAverage += 0.F * Integer.parseInt(subjects_G.get(i).getCredit());
+                }
+            }
+
+            allAverage = sgwAverage / getCredit_except_F_NP(subjects_M, subjects_G);
+        }
+        return allAverage;
+    }
+
+    public float averageMajorScore(ArrayList<Subject> subjects_M, ArrayList<Subject> subjects_G) {
+        float majorAverage = 0;
+        float sgwAverage = 0.F;
+        int majorCredit = 0;
+        for (int i = 0; i < subjects_M.size(); i++) {
+            if (!(subjects_M.get(i).getGrade().equals("F")) && !(subjects_M.get(i).getGrade().equals("NP"))) {
+                if (subjects_M.get(i).getGrade().equals("A+")) {
+                    sgwAverage += 4.5F * Integer.parseInt(subjects_M.get(i).getCredit());
+                } else if (subjects_M.get(i).getGrade().equals("A0")) {
+                    sgwAverage += 4.0F * Integer.parseInt(subjects_M.get(i).getCredit());
+                } else if (subjects_M.get(i).getGrade().equals("B+")) {
+                    sgwAverage += 3.5F * Integer.parseInt(subjects_M.get(i).getCredit());
+                } else if (subjects_M.get(i).getGrade().equals("B0")) {
+                    sgwAverage += 3.0F * Integer.parseInt(subjects_M.get(i).getCredit());
+                } else if (subjects_M.get(i).getGrade().equals("C+")) {
+                    sgwAverage += 2.5F * Integer.parseInt(subjects_M.get(i).getCredit());
+                } else if (subjects_M.get(i).getGrade().equals("C0")) {
+                    sgwAverage += 2.0F * Integer.parseInt(subjects_M.get(i).getCredit());
+                } else if (subjects_M.get(i).getGrade().equals("D+")) {
+                    sgwAverage += 1.5F * Integer.parseInt(subjects_M.get(i).getCredit());
+                } else if (subjects_M.get(i).getGrade().equals("D0")) {
+                    sgwAverage += 1.0F * Integer.parseInt(subjects_M.get(i).getCredit());
+                }
+            }
+
+        }
+        for(int j = 0; j < subjects_M.size(); j++){
+            majorCredit += Integer.parseInt(subjects_M.get(j).getCredit());
+        }
+
+        majorAverage = sgwAverage / majorCredit;
+
+        return majorAverage;
+    }
+
+    public void listOfSubjects(ArrayList<Subject> subjects_M, ArrayList<Subject> subjects_G) {
+        for (int i = 0; i < subjects_M.size(); i++) {
+            System.out.print("[전공] ");
+            System.out.print(subjects_M.get(i).getName());
+            System.out.print(",");
+            System.out.print(subjects_M.get(i).getCredit());
+            System.out.print(",");
+            System.out.println(subjects_M.get(i).getGrade());
+        }
+        for (int i = 0; i < subjects_G.size(); i++) {
+            System.out.print("[교양] ");
+            System.out.print(subjects_G.get(i).getName());
+            System.out.print(",");
+            System.out.print(subjects_G.get(i).getCredit());
+            System.out.print(",");
+            System.out.println(subjects_G.get(i).getGrade());
+        }
+
+    }
+
+//    public void Check(ArrayList<Subject> subjects_M, ArrayList<Subject> subjects_G){
+//        try {
+//            checkError(subjects_M,subjects_G);
+//        } catch (IllegalAccessException e) {
+//            throw e;
+//        }
+//    }
+
+    public void checkCreditError(ArrayList<Subject> subjects_M, ArrayList<Subject> subjects_G) {
+        for(int i = 0; i < subjects_M.size(); i++){
+            if(subjects_M.get(i).getName().length() > 10){
+                throw new IllegalArgumentException();
+            }
+        }
+
+        for(int i = 0; i < subjects_G.size(); i++){
+            if(subjects_G.get(i).getName().length() > 10){
+                throw new IllegalArgumentException();
+            }
+        }
+
+
+        for(int i = 0; i < subjects_M.size(); i++){
+            if(Integer.parseInt(subjects_M.get(i).getCredit()) < 1 || Integer.parseInt(subjects_M.get(i).getCredit()) > 4 ){
+                throw new IllegalArgumentException();
+            }
+        }
+
+        for(int i = 0; i < subjects_G.size(); i++){
+            if(Integer.parseInt(subjects_G.get(i).getCredit()) < 1 || Integer.parseInt(subjects_G.get(i).getCredit()) > 4 ){
+                throw new IllegalArgumentException();
+            }
+        }
+    }
+
+    public void checkGradeError(ArrayList<Subject> subjects_M, ArrayList<Subject> subjects_G) {
+        for(int i = 0; i < subjects_M.size(); i++){
+            if(subjects_M.get(i).getGrade().equals("A+") || subjects_M.get(i).getGrade().equals("A0") || subjects_M.get(i).getGrade().equals("B+") || subjects_M.get(i).getGrade().equals("B0")
+            || subjects_M.get(i).getGrade().equals("C+") || subjects_M.get(i).getGrade().equals("C0") || subjects_M.get(i).getGrade().equals("D+") || subjects_M.get(i).getGrade().equals("D0")
+            || subjects_M.get(i).getGrade().equals("F") || subjects_M.get(i).getGrade().equals("NP") || subjects_M.get(i).getGrade().equals("P")){
+
+            }else {
+                throw new IllegalArgumentException();
+            }
+        }
+    }
+}
diff --git a/src/main/java/gpacalc/Subject.java b/src/main/java/gpacalc/Subject.java
new file mode 100644
index 0000000..1c4ca2c
--- /dev/null
+++ b/src/main/java/gpacalc/Subject.java
@@ -0,0 +1,42 @@
+package gpacalc;
+
+public class Subject {
+    private String Name;
+    private String Credit;
+    private String Grade;
+
+    public Subject(String Name, String Credit, String Grade) {
+        this.Name = Name;
+        this.Credit = Credit;
+        this.Grade = Grade;
+    }
+
+
+    public String getName() {
+        return Name;
+    }
+
+    public void setName(String name) {
+        Name = name;
+    }
+
+    public String getCredit() {
+        return Credit;
+    }
+
+    public void setCredit(String credit) {
+        Credit = credit;
+    }
+
+    public String getGrade() {
+        return Grade;
+    }
+
+    public void setGrade(String grade) {
+        this.Grade = grade;
+    }
+}
+
+
+
+