Кубический сплайн

#include <iostream>
#include <math.h>
using namespace std;
int main()
{int n=5,i,j;double h;
double *X=new double [n];
double *Y=new double [n];
cout<<"X:\n";
for(i=0;i<n;i++)
    cin>>X[i];
cout<<"Y:\n";
for(i=0;i<n;i++)
    cin>>Y[i];
h=X[1]-X[0];
double *Q=new double [n];
double *D=new double [n];
double *A=new double [n];
double *B=new double [n];
double *C=new double [n];
double *a=new double [n];
double *b=new double [n];
Q[0]=0;Q[4]=0;
for(i=1;i<n-1;i++)
D[i]=((Y[i+1]-Y[i])/h)-((Y[i]-Y[i-1])/h);
A[1]=0;A[2]=h/6;A[3]=(h+h)/3;
B[1]=h/6;B[2]=(h+h)/3;B[3]=0;
C[1]=h/6;C[2]=(h+h)/3;C[3]=0;
for(i=1;i<n-1;i++)
    {cout<<A[i]<<" "<<B[i]<<" "<<C[i]<<" "<<D[i];
cout<<endl;}
a[1]=-C[1]/B[1];
a[2]=-C[2]/(B[2]+A[2]-a[1]);
a[3]=-C[3]/(B[3]+A[3]-a[2]);
b[1]=(-D[1])/(B[1]);
b[2]=(-D[2]-A[2]*b[1])/(B[2]+A[2]*a[1]);
b[3]=(-D[3]-A[3]*b[2])/(B[3]+A[3]*a[2]);
for(i=1;i<n-1;i++)
    cout<<"a"<<i<<"="<<a[i]<<" "<<"b"<<i<<"="<<b[i]<<endl;
Q[3]=b[3];
Q[2]=a[2]*Q[3]+b[2];
Q[1]=a[1]*Q[2]+b[1];
for(i=0;i<n;i++)
    cout<<"Q"<<i<<"="<<Q[i]<<endl;
for(i=1;i<n-1;i++)
    cout<<"S"<<i<<"[x]="<<Q[i]/6*h<<"(x-"<<X[i-1]<<")+"<<Q[i]*(Y[i-1]/h-Q[i-1]/6)<<X[i]<<"(x-"<<")+"<<Y[i]/6-Q[i]/6<<"(x-"<<X[i-1]<<")"<<endl;
system("pause");
return 0;}

B[1]=h/6;
...
C[1]=h/6;
...
a[1]=-C[1]/B[1];