Classical worm algorithm for several models

This is a demo code collection for classical worm algorithm.

Details of worm algorithm will be posted on Notion page in the future.

Note: Parallel tempering is not finished

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Dependency:

1. FFTW library
2. the lattice information. The library that generates lattices will be online in the further

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Ising model

almost done

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XY model

almost done

O(n) model

to add

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J-current model

to add

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phi^4 model

to add

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general flow model

to add