CPU Intensive Calculation Examples?

Question

I need a few easily implementable single cpu and memory intensive calculations that I can write in java for a test thread scheduler.

They should be slightly time con

Answer 1

Multiply two matrices. The matrices should be huge and stored on the disk.

String search. Or, index a huge document (detect and count the occurrence of each word or strings of alphabets) For example, you can index all of the identifiers in the source code of a large software project.

Calculate pi.

Rotate a 2D matrix, or an image.

Compress some huge files.

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