372. Super Pow - cocoder39/coco39_LC GitHub Wiki

class Solution {
public:
    int superPow(int a, vector<int>& b) {
        if (b.empty()) {
            return 1;
        }
        
        const int base = 1337;
        int last_digit = b.back();
        b.pop_back();
        return powmod(superPow(a, b), 10, base) * powmod(a, last_digit, base) % base;
    }
private:
    int powmod(int a, int k, const int base) {
        a %= base;
        int res = 1;
        for (int i = 0; i < k; i++) {
            res = (res * a) % base;
        }
        return res;
    }
};