Find Jobs
Hire Freelancers

Encrypt & Decrypt

$30-5000 USD

Completed
Posted about 21 years ago

$30-5000 USD

Paid on delivery
program written in C and contains the following: 1. Read in a message and an encryption key from the keyboard; 2. Show the given message; 3. Encrypt the given message using the encryption key and show the encoded message on the screen; 4. Decrypt the encoded message using the same encryption key back to the original and show the decrypted message. This program takes two things from the keyboard. This is a message and an encryption key. - The message can only contain printable characters. The maximum number of lines accepted is 6 and the maximum number of characters each line can contain is 128. If the number of lines entered is less than the constant 6, an empty line (only consisting of a single carriage return) is used to terminate the message. Otherwise, only 6 lines of the message will be taken. - The encryption key is a numerical value in the range 1 to 72. If an invalid encryption key is entered the program will keep asking the use to re-enter a valid key until the user does so. The Encryption Algorithm Any character (called target character) in the message will be replaced by another character (called new character) that is generated from the target character by shifting it encryption key number of places along the ASCII code set, using the following formula new = (target - 32 + key) % 95 + 32 The Decryption Algorithm: Any character (called target character) in the encoded message will be replaced by another character (called new character) that is generated from the target character by shifting it back encryption key number of places along the ASCII code set, using the following formula: new = (target + 63 - key) % 95 + 32 also to note: ASCII characters range from 32 - 127 ## Deliverables 1) well coded and styled and commented single source file in C 3) no need for an executable ## Platform 2) platform Linux/Unix
Project ID: 2925877

About the project

2 proposals
Remote project
Active 21 yrs ago

Looking to make some money?

Benefits of bidding on Freelancer

Set your budget and timeframe
Get paid for your work
Outline your proposal
It's free to sign up and bid on jobs
Awarded to:
User Avatar
See private message.
$2 USD in 14 days
4.9 (4 reviews)
0.3
0.3
2 freelancers are bidding on average $10 USD for this job
User Avatar
See private message.
$17 USD in 14 days
3.6 (11 reviews)
3.8
3.8

About the client

Flag of AUSTRALIA
Australia
5.0
3
Member since Oct 6, 2002

Client Verification

Thanks! We’ve emailed you a link to claim your free credit.
Something went wrong while sending your email. Please try again.
Registered Users Total Jobs Posted
Freelancer ® is a registered Trademark of Freelancer Technology Pty Limited (ACN 142 189 759)
Copyright © 2024 Freelancer Technology Pty Limited (ACN 142 189 759)
Loading preview
Permission granted for Geolocation.
Your login session has expired and you have been logged out. Please log in again.