#include <iostream>
#include <math.h>
using namespace std;
 
const float pi = 3.141592f;
 
template<typename T>
float GetDerivative(T func, float val, float eps)
{
	return (func(val + eps) - func(val)) / eps;
}
 
int main()
{
	auto sinRad = [](float rad){return sin(rad);};
	auto sinDeg = [](float deg){return sin(deg / 180.0f * pi);};
 
	float eps = 1e-5f;
	std::cout << "dsinRad(x)/dx|0 = " << GetDerivative(sinRad, 0.0f, eps) << "\n";
	std::cout << "dsinDeg(x)/dx|0 = " << GetDerivative(sinDeg, 0.0f, eps) << "\n";
	return 0;
}

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