More Problems

• Write a program to check if a string is a valid date in the format YYYY-MM-DD.
• Write a program to find the first non-repeating digit in a string.
• Write a program to implement a simple online chat application.
• Write a program to check if a number is a happy number using the tortoise and hare method.
• Write a program to find the maximum length of a palindromic substring in a string.
• Write a program to implement a basic online feedback system for products.
• Write a program to check if a string is a valid time in the format HH:MM
• Write a program to implement a binary search tree with insertion, deletion, and traversal operations.