<link href="//maxcdn.bootstrapcdn.com/bootstrap/4.1.1/css/bootstrap.min.css" rel="stylesheet" id="bootstrap-css">
<script src="//maxcdn.bootstrapcdn.com/bootstrap/4.1.1/js/bootstrap.min.js"></script>
<script src="//cdnjs.cloudflare.com/ajax/libs/jquery/3.2.1/jquery.min.js"></script>
<!------ Include the above in your HEAD tag ---------->
<!DOCTYPE html>
<html>
<body>
<script>
add(4, 3);
function hm(){
var lk=0;
}
function add(a, b) {
console.log(a + b)
lk=a+b
multi(a,b)
hm()
}
function multi(a,b){
console.log(a*b)
lk+=a*b
sub(a,b)
}
function sub(a,b){
console.log(a-b)
lk+=a-b
}
alert(lk)
console.log(lk)
</script>
</body>
</html>