6. ZigZag Conversion
The string "PAYPALISHIRING" is written in a zigzag pattern on a given number of rows like this: (you may want to display this pattern in a fixed font for better legibility)
P A H N
A P L S I I G
Y I R
And then read line by line: "PAHNAPLSIIGYIR"
Write the code that will take a string and make this conversion given a number of rows:
string convert(string text, int nRows);
convert("PAYPALISHIRING", 3) should return "PAHNAPLSIIGYIR".
My Solution
class Solution(object):
def convert(self, s, numRows):
"""
:type s: str
:type numRows: int
:rtype: str
"""
if numRows == 1:
return s
r, dict_s = '', {}
for i in range(len(s)):
row = i % (numRows + numRows - 2)
if row >= numRows:
row = numRows + numRows - 2 - row
if row in dict_s.keys():
dict_s[row] = dict_s[row] + s[i]
else:
dict_s[row] = s[i]
for i in range(max(dict_s.keys())+1):
r = r + dict_s[i]
return r
Reference (轉(zhuǎn))
class Solution(object):
def convert(self, s, numRows):
"""
:type s: str
:type numRows: int
:rtype: str
"""
if numRows == 1 or numRows >= len(s):
return s
L = [''] * numRows
index, step = 0, 1
for x in s:
L[index] += x
if index == 0:
step = 1
elif index == numRows -1:
step = -1
index += step
return ''.join(L)
