More Problems

• Write a program to check if a number is a happy number using a function.
• Write a program to implement a basic library management system.
• Write a program to find the longest substring that contains at most two distinct characters.
• Write a program to check if a string is a valid password according to certain rules.
• Write a program to implement a simple calculator that can perform basic arithmetic operations.
• Write a program to find the total number of words in a text file.
• Write a program to check if two numbers are co-prime.
• Write a program to implement a simple to-do list application with priorities.