p113_7.cpp

来自「常用算法代码」· C++ 代码 · 共 25 行

#include<iostream>
using namespace std;

double countFx(int x,int p) {
	if(p==0)return 0;
	if(p==1)return x;
	float y1 = countFx(x, p-1);
	float y2 = countFx(x, p-2);

	if(p%2)	return y1 + (y2-y1)*(x*x)/((2*p-1)*(2*p-2));

	return y1 - (y1-y2)*(x*x)/((2*p-1)*(2*p-2));
}

int main() {
	double x;
	int n;
	
	cout<<"请输入x和n：";
	cin>>x>>n;

	cout<<"f("<<x<<")="<<countFx(x,n)<<endl;

	return 0;
}