simple way of encrypting message is to rearrange its characters one way to rearrange the characters is to pick out the characters at even indicesput them first in the encrypted stringand follow them by the odd characters for examplethe string message would be encrypted as msaeesg because the even characters are msae (at indices and and the odd characters are esg (at indices and (awrite program that asks the user for string and uses this method to encrypt the string (bwrite program that decrypts string that was encrypted with this method more general version of the above technique is the rail fence cipherwhere instead of breaking things into evens and oddsthey are broken up by threesfours or something larger for instancein the case of threesthe string secret message would be broken into three groups the first group is sr sgthe characters at indices and the second group is eemsethe characters at indices and the last group is cteathe characters at indices and the encrypted message is sr sgeemsectea (awrite program the asks the user for string and uses the rail fence cipher in the threes case to encrypt the string (bwrite decryption program for the threes case (cwrite program that asks the user for stringand an integer determining whether to break things up by threesfoursor whatever encrypt the string using the rail-fence cipher (dwrite decryption program for the general case in calculusthe derivative of is the derivative of is the derivative of is this pattern continues write program that asks the user for input like ^ or ^ and prints the derivative for exampleif the user enters ^ the program should print out ^ in algebraic expressionsthe symbol for multiplication is often left outas in + or ( + computers prefer those expressions to include the multiplication symbollike * + * or *( + write program that asks the user for an algebraic expression and then inserts multiplication symbols where appropriate