For simplicity consider the case where: |K| = 2 and |M| = 4 (i.e the size of the keys is 2 characters and the size of the message is 4 characters). Show that the Vigenere cipher is not EAV-secure (as per Definition 3.8 of textbook). As discussed in class, in order to show this you need to describe an adversary who breaks the indistinguishability experiment with probability greater than 1/2 + negl(n).