<s>[INST] #ifndef __MATHS_H__
#define __MATHS_H__

#include <cmath>
#include <iostream>

namespace math {

    template <typename T>
    T gcd(T a, T b) {
        while (b != 0) {
            T temp = b;
            b = a % b;
            a = temp;
        }
        return a;
    }

    template <typename T>
    T lcm(T a, T b) {
        return (a * b) / gcd(a, b);
    }

    template <typename T>
    T factorial(T n) {
        if (n <= 1)
            return 1;
        return n * factorial(n - 1);
    }

    template <typename T>
    T ncr(T n, T r) {
        if (r > n)
            return 0;
        return factorial(n) / (factorial(r) * factorial(n - r));
    }

    template <typename T>
    T fibonacci(T n) {
        if (n <= 1)
            return n;
        return fibonacci(n - 1) + fibonacci(n - 2);
    }

    template <typename T>
    T pow(T a, T b) {
        T result = 1;
        for (T i = 0; i < b; i++) {
            result *= a;
        }
        return result;
    }
}

#endif

What are the potential issues with this C++ code snippet?[/INST]