# Caesar's Complication

Author: GabiTulbaContest: TJCTF 2018

## Problem statement:

King Julius Caesar was infamous for his wordsearch solving speed.

## My opinion:

Even if the idea of this challenge was pretty straight forward, I still found it very frustrating.

## Understanding the challenge:

First of all, it was clear from the challenge’s name that the encryption was a Caesar Cipher with some arbitrary shift key, and also the statement explicitly said that the ciphertext was a Word Search table, so to search for the flag we just needed some code to check for the string that starts with

`tjctf{`

and ends with`}`

in all 8 directions for every possible key.

## The code:

```
mat=[list(x) for x in open('ciphertext').read().split('\n')]
dirx=[0,1,1,1,0,-1,-1,-1]
diry=[1,1,0,-1,-1,-1,0,1]
def Check(x,y,d):
s=''
while(x<len(mat) and y<len(mat[x]) and x>0 and y>0):
s+=mat[x][y]
x+=dirx[d]
y+=diry[d]
if(s.startswith('tjctf{') and s.endswith('}')):
print 'Possible flag found:',s
return
def Search():
for x in range(len(mat)):
for y in range(len(mat[x])):
for d in range(8):
Check(x,y,d)
def Shift():
for i in range(len(mat)):
for j in range(len(mat[i])):
if(mat[i][j]=='{' or mat[i][j]=='}'):
continue
elif(mat[i][j]=='z'):
mat[i][j]='a'
else: mat[i][j]=chr(ord(mat[i][j])+1)
for i in range(26):
print 'Key:',i
Search()
Shift()
```

## Finding the flag:

The python code gave the following output:

Key: 0

Key: 1

…

Key: 8

Possible flag found: tjctf{idesofmarch}

Key: 9

…

Key: 25

So the flag was very easy to find:
Flag: **tjctf{idesofmarch}**