Programming in the minimal two-dimensional esoteric programming language 1L_a is pretty difficult, as there are only a few instructions. However, using some creative strategy, 1L_a has been proved to be Turing-Complete.
1L_a was designed by Scott Feeney. Released in 2005, it is the first member to be implemented in the 1L_a family. It's well known due to its simplicity.
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