Xorist 101

xorist.c

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

#define LENGTH 20
int main()
{
    char const plainone[LENGTH] = "BASIC XOR CRYPTO";
    char const plaintwo[LENGTH] = "WINKWINKWINKWINK";
    char xor[LENGTH];
    int i;

    for(i = 0; i < LENGTH; ++i) {
        xor[i] = (char)(plainone[i] ^ plaintwo[i]);
    }

    printf("Input: %s\nKey: %s\n\nXOR: ", plainone, plaintwo);

    for(i = 0; i < LENGTH; ++i) {
        printf("%02X ", xor[i]);
    }

    printf("\n");
    return 0;
}