K-th Digit of aᵇ

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Compute aᵇ and return its k-th digit from the right. Peeling digits is easy once you have the number, but the number can be huge. 9⁹⁹ has 95 digits.

Choose the right tool:

Python integers are arbitrary-precision, so a ** b just works
JavaScript has BigInt: BigInt(a) ** BigInt(b)
C++ / Java need a manual digit array (grade-school multiplication)

Then the k-th digit from the right is (value / 10^(k−1)) % 10, or simply index the string from the end.