#include"neel.h"
float fact(float);
void main()
{
float x[100],y[100][100],i,j,k,h,xi,s,p;
int n;
clrscr();
printf("enter the total no of variable:");
scanf("%d",&n);
for(i=0;i<n;i++)
{
printf("enter x[%.0f]:",i);
scanf("%f",&x[i]);
printf("enter y[%.0f]:",i);
scanf("%f",&y[0][i]);
}
for(j=0;j<n-1;j++)
{
for(k=0;k<n-1;k++)
{
if(k<=n-2)
{
y[j+1][k] = y[j][k+1] - y[j][k];
}
}
}
printf("\nenter the unknown x:");
scanf("%f",&xi);
s = 0;
for(j=1;j<=n-1;j++)
{
p = 1;
for(k=1;k<=j;k++)
{
p = p*(xi-x[k-1]);
}
s = s+ p*y[j][0]/fact(j);
}
s = s + y[0][0] ;
printf("\nresult:%f",s);
getch();
}
float fact(float x)
{
int p,f=1;
for(p=x;p>=1;p--)
f= f*p;
return f;
}