1.2.3.3 while/break/continue

典型的C式While循环（Mandelbrot问题）：

In [13]:

z = 1 + 1j
while abs(z) < 100: 
    z = z**2 + 1
z

Out[13]:

(-134+352j)

更高级的功能

bread 跳出for/while循环：

In [103]:

z = 1 + 1j
while abs(z) < 100:
    if z.imag == 0:
        break
    z = z**2 + 1
    print z

(1+2j)
(-2+4j)
(-11-16j)
(-134+352j)

continue 继续下一个循环迭代：

In [101]:

a = [1, 0, 2, 4]
for element in a:
    if element == 0:
        continue
    print 1. / element

1.0
0.5
0.25