#
# A program that shows that list members value might be changed 
# in a function + testing
#
# function 'square' squares all the elements of the list x
#

def square(x):
    n=len(x)
    for i in range(n):
        x[i]=x[i]*x[i]

def test1():
    print "TEST1"
    x=[1,2,3,4,5]
    print "the input list: \t  %s" % x
    square(x)
    print "the list after 'square' call:%s" % x

def test2():
    print "TEST2"
    x=[0,0,0]
    print "the input list: \t   %s" % x
    square(x)
    print "the list after 'square' call:%s" % x

def test3():
    print "TEST3"
    x=[-1,-2,-3]
    print "the input list: \t   %s" % x
    square(x)
    print "the list after 'square' call:%s" % x

test1()
test2()
test3()