Write a program using c++, to encrypt and (then decrypt) using Playfair cipher. The program should prompt the user to input a key word to generate the Key Grid. In addition, the user must input plaintext (ciphertext) and the program should display the corresponding cipher text (plaintext). And describe the algorithm.

.lntroduction( 50 words) .Define management-paraphrase a quote from a reputable

Write a Python program that prompts the user to create a user account and checks whether the provided user name and password are legal. Note: a user name should start with a letter and only consists of letters and numbers. The length should be between 6 and 12; a password should start with a letter and only consists of letters, numbers and the underscore symbol "_". The length should be between 8 to. 16.

Write a Java program to count the occurrence of each character in a given string.