Question

construct a turing machine to compute x-y where x and y are natural numbers

Answer 1

First we convert first zero of smaller number to x then we convert first zero of greater number to x.

Then same is done with second zero of both numbers. When all zeroes of smaller number has been converted to x, the remaining number of zeros is machine gives us our answer.

This turing machine will work only if larger number is on right hand side of c.

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