Question

Given that A to Z are mapped to integers 0-25 as follows.

A:0, B:1, C:2, D:3, E:4, F:5, G:6, H:7, I: 8, J: 9, K:10, L:11, M:12, N:13, O:14, P:15, Q:16, R:17, S:18, T:19, U:20, V:21, W:22, X:23, Y:24, Z:25.

Encrypt the following message using Vigenere Cipher with key: CIPHER

THISQUIZISEASY

What is the ciphertext? Show your work.

PLEASE HELP

Answer 1

Message : THISQUIZISEASY

Cipher : CIPHER

message

T

H

I

S

Q

U

I

Z

I

S

E

A

S

Y

key

C

I

P

H

E

R

C

I

P

H

E

R

C

I

encryption

V

P

X

Z

U

L

K

H

X

Z

I

R

U

G

Encryption is done using Vignere Table : https://media.geeksforgeeks.org/wp-content/cdn-uploads/Vigen%C3%A8re_square_shading.png

The row selected is Key letter and column to be used is message.
For example, for message = T, key = C the value using vignere table is found out to be V.

The cipher text generated is : VPXZULKHXZIRUG (2115232520111072325817206)

Please look at the working below as well.

Please comment in case of doubts and queries.
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