The most efficient way to implement an integer based power function pow(int, int)

by

Exponentiation by squaring.

int ipow(int base, int exp)
{
    int result = 1;
    for (;;)
    {
        if (exp & 1)
            result *= base;
        exp >>= 1;
        if (!exp)
            break;
        base *= base;
    }

    return result;
}

This is the standard method for doing modular exponentiation for huge numbers in asymmetric cryptography.

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