<script>
// Javascript program to compute sum of digits in
// number.
/* Function to get sum of digits */
function getSum(n)
{
var sum = 0;
while (n != 0) {
sum = sum + n % 10;
n = parseInt(n / 10);
}
return sum;
}
// Driver code
var n = 687;
document.write(getSum(n));
</script>