练习3-3
Python提供了一个内置函数len,返回一个字符串的长度。所以len('allen')的值是5.
编写一个函数 right_justify,接收一个字符串形参s,并打印出足够的前导空白,以达到最后一个字符显示在第70列上。
解答如下图:
运行结果如下:
练习3-5
编写一个函数,绘制如下的表格:
def do_twice(f):
f()
f()
def do_four(f):
do_twice(f)
do_twice(f)
def print_beam():
print '+ - - - -',
def print_post():
print '| ',
def print_beams():
do_twice(print_beam)
print '+'
def print_posts():
do_twice(print_post)
print '|'
def print_row():
print_beams()
do_four(print_posts)
def print_grid():
do_twice(print_row)
print_beams()
print_grid()
运行结果如下: