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 1:
Input: a = 2, b = [3]
Output: 8
Explanation:
The array b = [3] represents the exponent 3. Therefore, a3 = 23 = 8, so the result is 8.
Example 2:
Input: a = 2, b = [1,0]
Output: 1024
Explanation:
The array b = [1, 0] represents the exponent 10. Therefore, a10 = 210 = 1024, so the result is 1024.
Example 3:
Input: a = 1, b = [4,3,3,8,5,2]
Output: 1
Explanation:
The array b = [4, 3, 3, 8, 5, 2] represents a positive exponent. Since a = 1, any positive power of 1 is 1. Therefore, the result is 1.
Constraints:
1 <= a <= 231 - 11 <= b.length <= 20000 <= b[i] <= 9b does not contain leading zeros.