main.cpp

易学c++源码

#include <iostream>
#include <math.h>
using namespace std;
double a,b,c;
double func(double n)
{
	return a*pow(n,2)+b*n+c;
}
void main()
{
	double d,e,f,n;
	cin >>d >>e >>f >>n;
	a=(f-2*e+d)/2;
	b=e-a-d;
	c=d;
	cout <<func(n) <<endl;
}