Lagrange Interpolation Method C++

#include<iostream>
#include<bits/stdc++.h>
using namespace std;

int main()
{
    double a[10],b[10];
    int n,i,j;
    double x,X,Y,ans;
    double sum=0.0;
    cout<<"Enter how many data do u want?";
    cin>>n;
    cout<<"Enter the value of x & y";
    cout<<"\nX\tY\n";
    for(i=0;i<n;i++)
    {
        cin>>a[i]>>b[i];
    }
    cout<<"Enter the value of desire X : ";
    cin>>x;
    for(i=0;i<n;i++)
    {
        X=1;
        Y=1;
        for(j=0;j<n;j++)
        {
            if(j!=i)
            {
                X=X*(x-a[j]);
                Y=Y*(a[i]-a[j]);
            }
        }
        ans=(X/Y)*b[i];
        sum=sum+ans;
    }
    cout<<"Answer is : " <<sum<<endl;
    return 0;
}

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About Ashadullah Shawon

I am Ashadullah Shawon. I am a Software Engineer. I studied Computer Science and Engineering (CSE) at RUET. I Like To Share Knowledge. Learn More: Click Here