# Arup Guha
# 6/4/2024
# Illustrating both function calls and how lists are passed into functions.

def add(a,b):
    return a + b

def changelist(mylist):
    for i in range(len(mylist)):
        mylist[i] += 1

def main():

    # Illustrating pass by value for integers.
    print(add(3,6))
    x = add(3,6)
    print(x)
    y = 4
    z = add(x, y)
    print(z)
    w = add(3+x, 2-y)
    print(w)

    # Showing list passed by reference.
    a = [1,2,3]
    print(a)
    changelist(a)
    print(a)

main()