lagrange's interpolation

#include<stdio.h>
#include<conio.h>
void main()
{
int a=1,i,j,n;
float ans,s,x[10],y[10],prodfunc,sum;

printf("How many terms of x and y Entered: ");
scanf("%d",&n);

printf("Enter values of x:- \n");
for(i=0;i<n;i++)
{
scanf("%f",&x[i]);
}
printf("Enter values of y:- \n");
for(j=0;j<n;j++)
{
scanf("%f",&y[j]);
}
sum=0;
printf("Enter the value of x which is to be found: ");
scanf("%f",&ans);

for(i=0;i<n;i++)
{
prodfunc=1;
for(j=0;j<n;j++)
{
if(i!=j)
{
prodfunc=(prodfunc*(ans-x[j]))/(x[i]-x[j]);
}
}
sum=sum+(y[i]*prodfunc);
}
printf("For y(%f)= %f",ans,sum);
getch();
}