Leetcode | | ZigZag conversion Problems

Problem:

The string "Paypalishiring" is written with a zigzag pattern on a given number of rows like this: (You could want to display T  His-pattern in a fixed-font for better legibility) p   a   H-   NA p L S i i GY   i   RAnd then-read line by line: "Pahnaplsiigyir" Write the code that would take a string and make this conversion given a number of rows:string convert (str ing text, int nRows); CONVERT ("Paypalishiring", 3) should return "Pahnaplsiigyir".

Thinking:

(1) Read the test instructions, rearrange the strings according to the "Z" shape, and then link them to the output.

(2) There is no idea of disintegration, you can enumerate a few simple examples to find the law.

A: 2 rows, 1 to N of the sort
1 3 5 7 9 ...
2 4 6 8 10 ...

Two: 3 Rows of time, 1 to n sort of
1 5 9 ...
2 4 6 8 10 ...
3 7 11 ...

Three: 4 rows of time, 1 to n sort of
1 7 13 ...
2 6 8 12 14 ...
3 5 9 11 15 ...
4 10 16 ...

Is this the law? If not found, you can continue to write 5 rows of case. Soon you'll be able to find patterns. This is a way to solve the problem. When we have a difficult problem, let's consider the simple situation and see if we can find a pattern. This topic, we have written to these special cases, we find the following law, here we assume that we are divided into M-row:
1 row I starting from I
2 The interval of two numbers in row i is 2 (i-1), 2 (m-i) alternating

Code

Class Solution {public:    string Convert (string s, int nRows) {        int length = S.size ();               if ((nrows==1) | | | (nrows>=length))            return s;        string result;        for (int i=0;i<nrows;i++)        {            bool flag=true;            int j=i;           while (J<length)           {                              Result.push_back (s.at (j));               if ((i==0) | | | (i==nrows-1))                   j+=2* (nRows-1);               else               {                   if (flag)                   {                       j+=2* (nrows-i-1);                       Flag=false;                   }                   else                   {                       j+=2*i;                       flag=true;                   }                                  } else           }//while        }//for        return result;    convert};

Leetcode | | ZigZag conversion Problems