/*
 * Caesar cipher
 */

#include <stdio.h>
#include <stdlib.h>
#include <string.h>

#define N 128

void printbits(unsigned char v);

int main(int argc, char *argv[])
{
    unsigned char cleartext[] = "There are only 10 types of people";
    unsigned char key[]       = "xafshg%cjagec!f,kasjghfd kawjerc!";
    unsigned char ciphertext[N];
    unsigned char deciphertext[N];
    int i, l;
    l = strlen((const char *)cleartext);

    printf("%s\n\n", cleartext);

    for (i = 0; i < l; i++)
    {
        printbits(cleartext[i]);
    }
    printf("\n\n");
    
    for (i = 0; i < l; i++)
    {
        printbits(key[i]);
    }
    printf("\n\n");
    

    for (i = 0; i < l; i++)
    {
        ciphertext[i] = cleartext[i] ^ key[i];
        printbits(ciphertext[i]);
    }
    printf("\n\n");
    
    for (i = 0; i < l; i++)
    {
        deciphertext[i] = ciphertext[i] ^ key[i];
        printbits(deciphertext[i]);
    }
    deciphertext[l] = '\0';
    printf("\n\n");

    printf("%s\n", deciphertext);
    
    return 0;
}