More Problems

• Write a program to check if a string is a valid phone number format.
• Write a program to find the total number of islands in a 2D binary matrix.
• Write a program to implement a simple chat application with a user interface.
• Write a program to check if a number is a strong prime using its factors.
• Write a program to find the longest common subsequence in multiple sequences.
• Write a program to implement a binary search tree with balancing.
• Write a program to check if a number is a Harshad number using its digits.
• Write a program to find the longest contiguous subsequence with a given sum.