28 lines
545 B
Markdown
28 lines
545 B
Markdown
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# 条件控制语句
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## if...else
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最简单的**条件控制语句**。如果不需要else也可以**省略**。
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```python
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x = 10
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if x < 5:
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print("x比5小")
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else:
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print("x比5大")
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```
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## if...elif...else
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多重条件控制语句，仅需加几个`elif`
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```python
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num = 5 # 假设一个人在公司的等级
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if num == 3: # 判断num的值
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print 'boss'
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elif num == 2:
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print 'user'
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elif num == 1:
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print 'worker'
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elif num < 0: # 值小于零时输出
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print 'error'
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else:
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print 'roadman' # 条件均不成立时输出
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```
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