Ask ChatGPT to create faster or more concise versions of programs.

[Beliavsky]

Create a "make it faster" that check that the "faster" codes still compile, give the same results, and are faster.

Do the same thing with a "make it more concise" loop.

An example prompt is

Write a Fortran program that counts the number of primes below imax = 10^9 and prints the last one. Use the cpu_time intrinsic subroutine to count the time elapsed.

followed by make it faster prompts.