More Problems

• Write a program to implement a basic user authentication system with login/logout functionality.
• Write a program to check if a number is a happy number using a function.
• Write a program to find the longest common prefix among an array of strings.
• Write a program to implement a simple online task manager with deadlines.
• Write a program to check if two strings are isomorphic using a mapping.
• Write a program to find the maximum product of two integers in an array.
• Write a program to implement a basic file search utility.
• Write a program to check if a string is a valid JSON format.