function validzipcode()
{
  var x = document.getElementById('agree').checked;
  if (! x) {
    alert('You must agree to the privacy policy and participation terms.');
    return false;
  }
  if (document.getElementById('zipcode').value.length!=5) {
    alert('zipcode must be 5 digit number');
    document.getElementById('zipcode').focus;
    return false;
  }
  else {
    var x = document.getElementById('zipcode').value;
    if (x.length > 5)
    {
      alert("Zipcode must be 5 digit number");
      document.getElementById('zipcode').focus();
      return false;
    }
    else {
      for ( var i=0; i<x.length; i++ ) {
        if ( (x.charAt(i) < '0') || (x.charAt(i) > '9') ) {
          alert("Zipcode must be 5 digit number");
          document.getElementById('zipcode').focus();
          return false;
        }
      }
    }
  }
}

function s1ValidationWithEmail()
{
  var x = document.getElementById('agree').checked;
  if (! x) {
    alert('You must agree to the privacy policy and participation terms.');
    return false;
  }

  x = document.getElementById('email').value;
  var filter  = /^([a-zA-Z0-9_\.\-!#$%&'\*+\/=?^`{}\|\~])+\@(([a-zA-Z0-9\-])+\.)+([a-zA-Z0-9]{2,})$/;

  if (x == '' || x == null) {
    alert('Please fill in your email address.');
    return false;
  } else if (filter.test(x)) {
    return true;
  } else {
    errortext = 'Please input a valid email address.';
               
    alert(errortext);
    return false;
  }
}