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#include <cs50.h>
#include <stdio.h>
int main(int argc, string argv[])
{
int key = argv[1];
//if (argc != 2)
printf("%i\n", key);
}
/*Implement your program in a file called caesar.c in a directory called caesar.
Your program must accept a single command-line argument, a non-negative integer. Let’s call it
for the sake of discussion.
If your program is executed without any command-line arguments or with more than one command-line argument, your program should print an error message of your choice (with printf) and return from main a value of 1 (which tends to signify an error) immediately.
If any of the characters of the command-line argument is not a decimal digit, your program should print the message Usage: ./caesar key and return from main a value of 1.
Do not assume that
will be less than or equal to 26. Your program should work for all non-negative integral values of less than . In other words, you don’t need to worry if your program eventually breaks if the user chooses a value for that’s too big or almost too big to fit in an int. (Recall that an int can overflow.) But, even if is greater than , alphabetical characters in your program’s input should remain alphabetical characters in your program’s output. For instance, if is , A should not become \ even though \ is positions away from A in ASCII, per asciitable.com; A should become B, since B is
positions away from A, provided you wrap around from Z to A.
Your program must output plaintext: (with two spaces but without a newline) and then prompt the user for a string of plaintext (using get_string).
Your program must output ciphertext: (with one space but without a newline) followed by the plaintext’s corresponding ciphertext, with each alphabetical character in the plaintext “rotated” by k positions; non-alphabetical characters should be outputted unchanged.
Your program must preserve case: capitalized letters, though rotated, must remain capitalized letters; lowercase letters, though rotated, must remain lowercase letters.
After outputting ciphertext, you should print a newline. Your program should then exit by returning 0 from main.*/
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