57 lines
951 B
Python
57 lines
951 B
Python
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mat = [
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[1,1,1],
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[1,0,1],
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[1,1,1]
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]
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def setZeroes(mat):
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if not mat: return None
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rows = len(mat)
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cols = len(mat[0])
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def zeroUpward(i,j):
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if i<0: return
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else:
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mat[i][j]=0
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zeroUpward(i-1,j)
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def zeroDownward(i,j):
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if i>=rows: return
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else:
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mat[i][j]=0
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zeroDownward(i+1,j)
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def zeroLeft(i,j):
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if j<0: return
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else:
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mat[i][j]=0
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zeroLeft(i,j-1)
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def zeroRight(i,j):
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if j>=cols: return
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else:
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mat[i][j]=0
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zeroRight(i,j+1)
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# go over mat first time to add cells to set (without modify matrix)
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for i in range(0, rows):
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for j in range(0, cols):
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if mat[i][j]==0:
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zeroUpward(i,j)
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zeroDownward(i,j)
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zeroLeft(i,j)
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zeroRight(i,j)
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return mat
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setZeroes(mat)
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print(mat)
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