63 lines
1.0 KiB
Markdown
63 lines
1.0 KiB
Markdown
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---
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layout: page
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title: Rotate Image
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last_solved: 2020-06-11
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category: matrix
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leetcode_url: https://leetcode.com/problems/rotate-image/
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status: Solved
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---
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{% highlight python %}
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'''
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rotate 90 degree = transpose + flip horizontally
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https://www.geeksforgeeks.org/rotate-matrix-90-degree-without-using-extra-space-set-2/?ref=rp
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'''
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mat = [
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[1,2,3],
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[4,5,6],
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[7,8,9]
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]
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def rotateMatrix(mat):
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n = len(mat)
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for i in range(n):
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for j in range(i,n):
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tmp = mat[i][j]
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mat[i][j] = mat[j][i]
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mat[j][i] = tmp
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for row in mat:
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print(row)
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print("after second rotation")
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for i in range(n):
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for j in range(n//2):
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tmp = mat[i][j]
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mat[i][j] = mat[i][n-j-1]
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mat[i][n-j-1] = tmp
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for row in mat:
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print(row)
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return mat
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print(rotateMatrix(mat))
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# for row in mat:
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# print(row)
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{% endhighlight %}
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