Text Editor

Write a C++ program to implement a text editor that supports basic operations like append, delete, and cursor movement along with undo and redo functionality.

Example 1

  
Input: ["TextEditor", "append", "cursorRight", "append", "cursorLeft", "delete", "undo", "redo", "getText"]
[[], ["Hello"], [2], [" World"], [3], [2], [], [], []]
  
Output: [null, null, null, null, null, null, null, null, "Hell World"]
  
Explanation: 

      
TextEditor editor = new TextEditor();
      
editor.append("Hello");         // text = "Hello|" (cursor at end of text)
      
editor.cursorRight(2);          // can only move cursor right 0 positions
      
editor.append(" World");        // text = "Hello World|"
      
editor.cursorLeft(3);           // text = "Hello Wo|rld"
      
editor.delete(2);               // text = "Hello |rld"
      
editor.undo();                  // text = "Hello Wo|rld"
      
editor.redo();                  // text = "Hello |rld"
      
editor.getText();               // returns "Hell World"
    

Example 2

  
Input: ["TextEditor", "append", "append", "delete", "cursorLeft", "cursorRight", "undo", "getText"]
[[], ["ABC"], ["DEF"], [1], [5], [2], [], []]
  
Output: [null, null, null, null, null, null, null, "ABCDEF"]
  
Explanation: 

      
TextEditor editor = new TextEditor();
      
editor.append("ABC");           // text = "ABC|"
      
editor.append("DEF");           // text = "ABCDEF|"
      
editor.delete(1);               // text = "ABCDE|"
      
editor.cursorLeft(5);           // text = "|ABCDE"
      
editor.cursorRight(2);          // text = "AB|CDE"
      
editor.undo();                  // text = "ABCDEF|" (undoes the delete operation)
      
editor.getText();               // returns "ABCDEF"
    

Constraints

  
1 <= text.length <= 100
  
1 <= k <= 100
  
The editor initially starts with an empty text.
  
The undo and redo operations return the state of the editor before and after the corresponding operation.
  
At most 2000 calls will be made to all operations combined.
  
Time Complexity: O(1) amortized for all operations
  
Space Complexity: O(N) where N is the total length of all text operations