擅长:python、mysql、java
<p>您根本不需要嵌套检查,因为每个部分都有自己的条件</p>
<p>您还可以为每个条件使用中间变量,这将使其更易于在最终输出中使用</p>
<p>请注意,每个<code>if</code>在同一垂直缩进线上都有一个(可选)匹配的<code>else</code></p>
<pre><code># Get and check input
highway_number = int(input("Enter highway number: "))
if highway_number < 1 or highway_number > 999:
print (' {} is not a valid highway number'.format (highway_number))
quit()
# Type + serving
if highway_number > 100:
road_type = 'auxiliary'
serving = str(highway_number % 100)
else:
road_type = 'primary'
serving = ''
# Direction
if highway_number % 2 == 0:
going = 'east/west'
else:
going = 'north/south'
# Create output
output = ['I-{}'.format(highway_number), 'is', road_type + ',']
if serving:
output.extend(['serving', 'I-{},'.format(serving)])
output.extend(['going', going])
print(' '.join(output))
</code></pre>