Modular Exponentiation

Given three integers `base`, `exp`, and `mod`, compute `(base^exp) % mod` efficiently in `O(log exp)` time. ### Constraints - `1 <= base <= 10^9` - `0 <= exp <= 10^9` - `1 <= mod <= 10^9` ### Input Format A single line containing three space-separated integers `base exp mod`. ### Output Format Print the computed integer `(base^exp) % mod`.