Consider the following Scala program

What does this program will print if we make the following assumptions about the parameter passing modes for the parameters x and y of params:

1. both x and y are call-by-value

2. x is call-by-reference and y is call-by-value

3. x is call-by-value and y is call-by-name

4. x is call-by-reference and y is call-by-name

def params x Int, y Int) println(x); var z -1; params (z, z + 1); println (z)