[leetcode]ZigZag Conversion

题目：

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   NA P L S I I GY   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".

链接：https://oj.leetcode.com/problems/zigzag-conversion/

描述：纯模拟就行了

solution by python:

class Solution:    # @return a string    def convert(self, s, nRows):        strings = ['' for i in range(nRows)]        i = 0;row_index = 0        while i < len(s):            while i < len(s) and row_index < nRows:                strings[row_index] += s[i]                i+=1                row_index+=1            row_index = nRows-2            while i < len(s) and row_index > 0:                strings[row_index] += s[i]                i+=1                row_index-=1        return ''.join(strings)