Fortran · version 2018

Run Fortran 2018 online

Fortran 2018 — run it in a Firecracker microVM on ls-judge. Real toolchain, no wrapper.

Starter code

What you get in Fortran 2018

Clicking "Run now" opens the playground with this exact code and a matching test case — passes on first Run.

fortran
Fortran 2018
program solution
  implicit none
  integer :: n
  read(*,*) n
  write(*,'(i0)') n * 2
end program solution
stdin →21
expected →42
How it runs

How ls-judge runs Fortran 2018

Every submission is compiled and executed inside its own Firecracker microVM — the same isolation primitive AWS Lambda uses. No shared container, no shared kernel with other users' code. The Fortran 2018toolchain shipped with the microVM is the real thing (not a browser-side emulation): syscalls behave the way they do in production, and the compile / runtime behaviour matches what you would see on your own machine with that version installed.

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