paper1b_1.cpp

paper1b_1.cpp

#include <iostream>
#include <iomanip>
#include <cmath>
using namespace std;

int main()
{
	int m_upper;
	double x,B = 0.0,den;
	
	cout << "input m's upper limit :"; cin >> m_upper;
	if (m_upper < 0)
	{
		cout << "m's upper limit cannot be smaller than 0" << endl;
		return -1;
	}
	
	cout << "input x               :"; cin >> x      ;
	
	for(int m = 0;m<= m_upper;m++)
	{
		den = 1.0;
		for(int a = 1;a <= 2*m;a++)
		{
			den *= double(a);
		}
		B += pow(x,double(2*m)) / den;
	}
	cout << "B = ";
	cout << setiosflags(ios::fixed) << setprecision(3);
	cout << B;
	
	
	return 0;
}