使用C++编写牛顿插值法程序（可以输出差商表）

#include<iostream>
#include<cstdio> 
using namespace std;
double aver(int num,double x[],double y[],double aa){ 
	  double a[num];
	  a[0]=y[0];
	   cout<<"下面输出差商表"<<"\n";
	  for (int i=1;i<=num-1;i++){ 
	  	 for (int j=0;j<num-i;j++){ 
	  	 double temp1=y[j];
	  	 double temp2=y[j+1];
	  	 	 y[j]=(temp2-temp1)/(x[j+i]-x[j]);
	    cout<<y[j]<<" ";
	  	  }
	  	  a[i]=y[0];
	  	cout<<"\n"<<"\n";
	  }
	   double sum1=a[0];
	  for (int i=0;i<num-1;i++){ 
	  	   double sum2=1;
	     for (int j=0;j<=i;j++){ 
		     sum2=sum2*a[j+1]*(aa-x[j]);
		 }
		 sum1=sum1+sum2;  
	  }
	  cout<<"下面输出计算值"<<"\n";
	 cout<<sum1;
}
int main(){ 
    int num;
    cout<<"输入节点的个数"; 
    scanf("%d",&num);
    double x[num],y[num];
    for (int i=0;i<num;i++){ 
    	cout<<"输入第"<<i+1<<"个x的值"; 
	    scanf("%lf",&x[i]);
		cout<<"输入第"<<i+1<<"个y的值";
		scanf("%lf",&y[i]);
	}
	double aa;
	cout<<"输入要计算的值";
	cin>>aa;
	cout<<"\n";
	cout<<"下面输出插值节点表"<<"\n";
	for (int i=0;i<num;i++){ 
	    cout<<x[i]<<" ";
	} 
	cout<<"\n";
	for (int i=0;i<num;i++){ 
	    cout<<y[i]<<" ";
	} 
	cout<<"\n"<<"\n";
	aver(num,x,y,aa);
	return 0;  
}