1. The problem
The substitution cipher can be easily cracked from a simple method of frequency analysis. Frequency analysis is a measuring of counts a letter appears in a text. as E is the most frequently used letter in the alphabet, one can crack the code by finding the most frequently used letter in a code, and find out the key to read the code.

 

2. the solution

The solution I came up with is this.

– make a pattern of numbers. (e.g. 1-2-3-4-5)

– make a pattern of directions (e.g. left, right, left, right)

– Choose how to substitute letters (e.g. plus 1, therefore A=B, B=C)

– Apply these patterns to a code such as I like Pie.

Therefore the code for I like Pie will be

HNFOKOKB

#exploremaths

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