Practice/Google/Leetcode 2296. Design a Text Editor

Leetcode 2296. Design a Text Editor

CodingMust

Problem

Design and implement a text editor class that maintains a document with a movable cursor. Your editor should support the following operations:

• addText(text): Insert the given string at the current cursor position and move the cursor to the end of the inserted text
• deleteText(k): Delete up to k characters to the left of the cursor (like pressing backspace k times), return the actual number of characters deleted
• cursorLeft(k): Move the cursor k positions to the left (stop at the beginning if k is too large), return the last 10 characters to the left of the cursor after moving
• cursorRight(k): Move the cursor k positions to the right (stop at the end if k is too large), return the last 10 characters to the left of the cursor after moving

The cursor starts at position 0 (before any text).

Requirements

1. Implement a TextEditor class with the four methods described above
2. The deleteText method must return an integer representing how many characters were actually deleted
3. The cursorLeft and cursorRight methods must return a string containing at most the last 10 characters to the left of the cursor after the movement
4. Handle edge cases where operations would move the cursor beyond document boundaries
5. Efficiently handle insertion and deletion operations at the cursor position

Constraints

• The total number of characters inserted will not exceed 50,000
• At most 20,000 operations will be called
• 1 ≤ text.length ≤ 100 for addText
• 1 ≤ k ≤ 50,000 for deleteText, cursorLeft, and cursorRight
• All input strings consist of lowercase English letters
• Aim for efficient operations on the cursor position

Examples

Example 1:

` Operations: TextEditor editor = new TextEditor() editor.addText("hello") editor.deleteText(2) // returns 2 editor.cursorLeft(3) // returns "" editor.addText("world") editor.cursorRight(10) // returns "worldhel"

Explanation:

• After addText("hello"), text is "hello|" (| represents cursor)
• After deleteText(2), text is "hel|" and returns 2 (deleted "lo")
• After cursorLeft(3), cursor moves to "|hel" and returns "" (no chars to left)
• After addText("world"), text is "world|hel"
• After cursorRight(10), cursor moves to "worldhel|" and returns "worldhel" `

Example 2:

` Operations: TextEditor editor = new TextEditor() editor.addText("abcdefghijklmnop") editor.cursorLeft(5) // returns "abcdefghij" editor.deleteText(3) // returns 3 editor.cursorRight(2) // returns "abcdefghij"

Explanation:

• After addText, text is "abcdefghijklmnop|"
• After cursorLeft(5), cursor at "abcdefghijk|lmnop", returns last 10: "abcdefghij"
• After deleteText(3), text is "abcdefgh|lmnop", returns 3
• After cursorRight(2), cursor at "abcdefghij|mnop", returns "abcdefghij" `