58 lines
876 B
Markdown
58 lines
876 B
Markdown
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---
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layout: page
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title: Pow(x, n)
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last_solved: 2020-07-16
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category: bit manipulation
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leetcode_url: https://leetcode.com/problems/powx-n/
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status: Attempted
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---
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Problem
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-------
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```
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Implement pow(x, n), which calculates x raised to the power n (xn).
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Example 1:
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Input: 2.00000, 10
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Output: 1024.00000
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Example 2:
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Input: 2.10000, 3
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Output: 9.26100
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Example 3:
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Input: 2.00000, -2
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Output: 0.25000
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Explanation: 2-2 = 1/22 = 1/4 = 0.25
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```
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Solution
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----------
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Didn't quite get it to work. Do check out [Timonthy's explanation](https://www.youtube.com/watch?v=Twr5TD8Fvbo)
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{% highlight python %}
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def myPow(self, x: float, n: int) -> float:
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if n<0:
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x = 1/x
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n = n*-1
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output = 1
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while n>0:
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if n&1:
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print(n, x, output)
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output *= x
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n>>=1
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x=x*x
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return output
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{% endhighlight %}
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![image1]()
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