Given a 32-byte hexadecimal character array representing the AES-256 input key, execute the AES-256 algorithm, KeyExpansion() and output the xth (input) key-word of this 60-word sequence as a 4x2 hexadecimal array. You will need the SubBytes() function done in one of my previous Cody problems.

Refer to this link: https://csrc.nist.gov/csrc/media/publications/fips/197/final/documents/fips-197.pdf

For example:

key='e32868331fa8ef0138de0de85478346aec5e3912b6029ae71691c384237a3eeb';
x=58;%want key-word number 58 out of 60
w=['d0';'eb';'7c';'8a'];%58th key-word
Solve

Solution Stats

5 Solutions

3 Solvers

Last Solution submitted on Oct 11, 2025

Last 200 Solutions

Solution Comments

Show comments

Problem Recent Solvers3

William George Berken David Hill

Suggested Problems

More from this Author61

Community Treasure Hunt

Find the treasures in MATLAB Central and discover how the community can help you!

Start Hunting!