# This program finds the sum of squares of first n postive integers,
# where n is inputed by the user.


def main():
    print "This program finds the sum of squares of first n postive integers,",
    print "where n is inputed by the user."

    number=input("Please input any positive integer and press Enter:")

    answer=sumOfSquares(number)

    if answer != -1:
        print "The sum of squares of first",number,"positive integers is",answer
    else:
        print "Have a good day"


# Finds the sum of squares of first n postive integers
# returns -1 if the value n is not a positive integer,
# otherwise, returns the sum
def sumOfSquares(n):
    if type(n) != int:
        print "The value ",n,"is not an integer value.",
        print "Exiting the program ..." 
        return -1
    if n < 1:
        print "The value ",n,"is not positive.",
        print "Exiting the program ..."
        return -1
    sq = 0
    for k in range(n+1):
        sq += k*k
    return sq

main()