#include <cmath>
#include <iostream>
using namespace std;
template<typename T>
T parse(const char* prompt) {
T value{};
cout << prompt;
cin >> value;
cin.ignore(0x1000, '\n');
return value;
}
double product(const double x, const unsigned n) {
auto p = 1.0;
for (auto i = 2U; i <= n; ++i) {
const auto nx = x + 4.0;
p *= 1.0 + exp(i / -nx);
}
return p;
}
void show(const char* prompt, const double value) {
cout.precision(17);
cout << prompt << value << '\n';
}
int main() {
const auto n = parse<unsigned>("n: ");
const auto x = parse<double>("x: ");
const auto y = sin(0.01 * product(x, n));
show("y: ", y);
}