#include<stdio.h>
#include<cs50.h>
#include<string.h>
#include<ctype.h>
bool check_validity_key(string s);
int main(int argc, string argv[])
{
if (!check_validity_key(argv[1]))
{
printf("Key must contain only alphabetic characters\n");
}
int len = strlen(argv[1]);
string key = argv[1];
string plaintext = get_string (" Plaintext: ");
printf("ciphertext: ");
if(argc == 2)
{
if (len == 26)
{
for(int i = 0 ; i < len ; i++)
{
for (int j = i + 1 ; j < len ; j++)
{
if (key[i] == key[j])
{
printf("Key must not contain repeated letters\n");
return 1;
}
}
}
for ( int m = 'A'; m <= 'Z' ; m++)
{
key[m-'A'] = toupper(key[m-'A'])-m;
}
for (int k = 0,length=strlen(plaintext); k < length ; k++)
{
if(isalpha(plaintext[k]))
{
plaintext[k]= plaintext[k]+key[plaintext[k]-(isupper(plaintext[k]) ? 'A' : 'a')];
}
printf("%c",plaintext[k]);
}
printf("\n");
}
else
{
printf("Key must contain 26 letters\n");
return 1;
}
}
else
{
printf("Usage: ./substitution key\n");
return 1;
}
return 0;
}
bool check_validity_key(string s)
{
int len = strlen(s) ;
for(int i = 0 ; i < len ; i++)
{
if (!isalpha(s[i]))
{
return false;
}
}
return true;
}
errors i get :
:( handles lack of key
failed to execute program due to segmentation fault
:( handles invalid key length
timed out while waiting for program to exit
:( handles invalid characters in key
timed out while waiting for program to exit
:( handles duplicate characters in key
timed out while waiting for program to exit
:( handles multiple duplicate characters in key
timed out while waiting for program to exit
