******HI! THE FOLLOWING CODE NEEDS TO BE IN C PLEASE!!!!!*******. I am having difficulty solving this, thank you very much in advance!!

Program 1: Caesar Cipher In cryptography, a Caesar Cipher is one of the simplest and most widely known encryption techniques. It is a type of substitution cipher in which each letter in the plaintext is replaced by a letter some fixed number of positions down the alphabet. For example, with a left shift of 3, D would be replaced by A, E Would become B, and so on. The method is named after Julius Caesar, who used it in his private correspondence. wiki/Caesar cipher A B C D E F G H I ABCD EF In a Caesar Cipher, the encryption is performed against a key string, which is often just the 26 letters of the alphabet. An offset value is defined that consists of a positive or negative integer. The plaintext (the normal text) is encrypted, one letter at a time, by using that offset value in the following way: (a) the index position within the key string of the letter to be encrypted is determined, (b) the offset value is applied to that index in order to obtain a new index within the key string, (c) the character at the new index is written as the cipher text. For a simple example, let's assume the key string consists of the 26 letters of the alphabet plus a space