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".
Solution: divide the whole string into subsections. In this example, "PAYPALISHIRING" is divided to "PAYP;ALIS;HIRI;NG".Then we will first insert the start character of each subsection to the zigzag version. Then, insert the character next to first subsection, and the character previous to the next subsection.

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