Super Pow — LeetCode 372 Python Solution

The problem

Your task is to calculate ab mod 1337 where a is a positive integer and b is an extremely large positive integer given in the form of an array.

Example

Input

a = 2, b = [3]

Output

8

Python solution

class Solution:
    def superPow(self, a: int, b: List[int]) -> int:
        mod = 1337
        ans = 1
        for e in b[::-1]:
            ans = ans * pow(a, e, mod) % mod
            a = pow(a, 10, mod)
        return ans

Complexity

Pattern: Math and Number Theory

Find the closed form, the invariant, or the modular identity — and skip the loop entirely. LeetCode 372. Super Pow is filed here on both counts: the reference solution below belongs to the algorithm family this hub collects, and LeetCode tags it Math.

The math and number theory guide has the Python template for the pattern and the 485 LeetCode problems that use it.

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