function validate() {
   let weightArray=[2, 4, 8, 5, 10, 9, 7, 3, 6];
    let sum=0;
document.querySelector('#exercise>fieldset>div>button').addEventListener('click', validateNumber);

function validateNumber(){
    let input=document.querySelector('#exercise>fieldset>div>input').value;

    let lastDigit=input[input.length-1];
    for(i=0; i<9; i++){

        let temp1=input[i];
        let temp2=weightArray[i];

        sum+=temp1*temp2;
    }

    let reminder=sum%11;

    if(reminder===10){
        reminder=0;
    }
    let response=document.getElementById('response');

    if(+lastDigit===reminder){
response.textContent='This number is Valid!';
    }
    else{
        response.textContent='This number is NOT Valid!';

    }
}


}