diff --git a/src/main/java/com/unitime/feature/Editor.java b/src/main/java/com/unitime/feature/Editor.java
new file mode 100644
index 0000000..f0ae8c3
--- /dev/null
+++ b/src/main/java/com/unitime/feature/Editor.java
@@ -0,0 +1,173 @@
+package com.unitime.feature;
+
+import java.util.*;
+import com.unitime.UI.ResultView;
+import com.unitime.algorthm.Scheduler;
+
+public class Editor {
+
+    private List<List<Course>> schedules;
+    private List<Course> mandatoryList;
+    private List<Course> optionList;
+    private int goalCredit;
+    
+    private Scanner sc; 
+
+    // Constructor
+    public Editor(List<List<Course>> schedules, List<Course> mandatory, List<Course> optional, int credit, Scanner scanner) {
+        this.schedules = schedules;
+        this.mandatoryList = mandatory;
+        this.optionList = optional;
+        this.goalCredit = credit;
+        this.sc = scanner;
+    }
+
+    // Routing: send to function depending on its input
+    public void route(String input, List<List<Course>> currentSchedules) {
+        if (currentSchedules != null) {
+            this.schedules = currentSchedules;
+        }
+
+        input = input.toLowerCase().trim();
+
+        if (input.equals("quit")) quit();
+        else if (input.equals("edit")) editList(); 
+        else if (input.equals("next")) viewLoop(5);
+        else {
+            System.out.println("[Error] Invalid input. Going back to View Mode.");
+            viewLoop(0);
+        }
+    }
+
+    // 'next': loop to show 5 more schedules
+    private void viewLoop(int startIndex) {
+        int index = startIndex;
+        String nextInput;
+
+        while (true) {
+            ResultView rv = new ResultView();
+            nextInput = rv.printBatchAndGetInput(this.schedules, index, this.sc);
+
+            if (nextInput.equals("next")) {
+                if (index + 5 < schedules.size()) {
+                    index += 5;
+                } else {
+                    System.out.println("[Info] No more schedules to show.");
+                }
+                continue;
+            }
+            break; 
+        }
+        
+        route(nextInput, this.schedules); 
+    }
+
+    // 'edit': edit lists and send it back to InputHandler 
+    private void editList() {
+        System.out.println("[Edit Mode]");
+        modifyCourse(this.mandatoryList, this.optionList); 
+
+        System.out.println("Re-calculating schedules...");
+
+        Scheduler scheduler = new Scheduler();
+        this.schedules = scheduler.schedule(this.mandatoryList, this.optionList, this.goalCredit);
+    }
+
+    // helper of 'edit'
+    private void modifyCourse(List<Course> mandatory, List<Course> optional) {
+
+        InputHandler ih = new InputHandler();
+
+        while (true) {
+            System.out.println("\n------------------------------------------");
+            System.out.println(" Current Goal Credit: " + this.goalCredit);
+            System.out.println(" Mandatory: " + mandatory.size() + " courses");
+            System.out.println(" Optional : " + optional.size() + " courses");
+            System.out.println("------------------------------------------");
+            System.out.println("1. Add/Edit MANDATORY Courses");
+            System.out.println("2. Add/Edit OPTIONAL Courses");
+            System.out.println("3. Remove a Course");
+            System.out.println("4. Change Goal Credit");
+            System.out.println("0. Finish Editing (Run Scheduler)");
+            System.out.print("> Select: ");
+
+            String choice = sc.nextLine().trim();
+
+            // Add
+            if (choice.equals("1")) {
+                System.out.println("\n[Add to Mandatory] Type 'done' to finish.");
+                ih.inputLoop(sc, mandatory);
+            } 
+            else if (choice.equals("2")) {
+                System.out.println("\n[Add to Optional] Type 'done' to finish.");
+                ih.inputLoop(sc, optional);
+            } 
+            else if (choice.equals("3")) {
+                removeCourseHelper(mandatory, optional);
+            } 
+            else if (choice.equals("4")) {
+                System.out.print("Enter new max credit: ");
+                try {
+                    int newCredit = Integer.parseInt(sc.nextLine().trim());
+                    if (newCredit > 0) {
+                        this.goalCredit = newCredit;
+                        System.out.println("Goal credit updated.");
+                    } else {
+                        System.out.println("Credit must be positive.");
+                    }
+                } catch (Exception e) {
+                    System.out.println("Invalid number.");
+                }
+            } 
+            else if (choice.equals("0")) {
+                break;
+            } 
+            else {
+                System.out.println("Invalid choice.");
+            }
+        }
+    }
+
+    // helper of 'edit': remove
+    private void removeCourseHelper(List<Course> mandatory, List<Course> optional) {
+        System.out.println("\n[Remove Course]");
+        System.out.println("1. From Mandatory");
+        System.out.println("2. From Optional");
+        System.out.print("> Select list: ");
+        String listType = sc.nextLine().trim();
+
+        List<Course> target = null;
+        if (listType.equals("1")) target = mandatory;
+        else if (listType.equals("2")) target = optional;
+        else {
+            System.out.println("Canceled.");
+            return;
+        }
+
+        if (target.isEmpty()) {
+            System.out.println("This list is empty.");
+            return;
+        }
+
+        for (int i = 0; i < target.size(); i++) {
+            System.out.println("[" + i + "] " + target.get(i).getName());
+        }
+
+        System.out.print("Enter index to remove (or -1 to cancel): ");
+        try {
+            int idx = Integer.parseInt(sc.nextLine().trim());
+            if (idx >= 0 && idx < target.size()) {
+                Course removed = target.remove(idx);
+                System.out.println("Removed: " + removed.getName());
+            } else if (idx != -1) {
+                System.out.println("Invalid index.");
+            }
+        } catch (Exception e) {
+            System.out.println("Invalid input.");
+        }
+    }
+
+    public void quit(){
+        System.out.println("[Bye] Closing system...");
+    }
+}
\ No newline at end of file
diff --git a/src/main/java/com/unitime/feature/InputHandler.java b/src/main/java/com/unitime/feature/InputHandler.java
index 842bc42..82a71fd 100644
--- a/src/main/java/com/unitime/feature/InputHandler.java
+++ b/src/main/java/com/unitime/feature/InputHandler.java
@@ -63,12 +63,10 @@ public InputHandler() {
         System.out.println("==========================================");
         System.out.println("Finding timetables...");
         System.out.println("==========================================");
-
-        sc.close();
     }
 
     // Get user input
-    private void inputLoop(Scanner sc, List<Course> targetList) {
+    public void inputLoop(Scanner sc, List<Course> targetList) {
         System.out.println("------------------------------------------------------------------");
         System.out.println("Format: Name / Credit / Time");
         System.out.println("Example: Data Structure / 3 / Mon 12:30 14:00");
@@ -143,7 +141,7 @@ private void inputLoop(Scanner sc, List<Course> targetList) {
     }
 
     // Change time into minutes
-    private int parseMin(String t) throws Exception {
+    public int parseMin(String t) throws Exception {
         try {
             String[] hhmm = t.split(":");
             if (hhmm.length != 2) {