LAGRANGE'S INTERPOLATION IN C

//program to implement lagranges interpolation.
#include<stdio.h>
int main()
{

 int i,j,n;

printf("\n Enter the number of entries :\n);
scanf("%d",&n);

float x[n],y[n],nr,dr,xv,yv=0.0;

printf("\n Enter the values of x and y :\n \n);
  for(i=0;i<n;i++)
    scanf("%f%f",&x[i],&y[i]);

printf("\n Enter the the value of x to find y :\n);
scanf("%f",&xv);

  for(i=0;i<n;i++)

 {
   nr=1;

   dr=1;

    for(j=0;j<n;j++)

    {
       if(j!=i)
       {  nr=nr*(xv-x[j]);
          dr=dr*(x[i]-x[j]);
        }
    }
    yv=yv+((nr/dr)*y[i]);
 }
printf("The value of y for x= %f is y= %f \n ",xv,yv);

return 0;
}