Leetcode-ZigZag Conversion

http://oj.leetcode.com/problems/zigzag-conversion/

题目描述

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".

AC代码

#include <iostream>
#include <cstring>
#include <string.h>
#include <cstdio>
#include <cstdlib>
#include <vector>

using namespace std;

string convert(string s, int nRows)
{
        if(nRows <= 1 || s.length() < 2)
            return s;
        string *arr = new string[nRows];
        int nCount = 2 * (nRows - 1);

        for(int i = 0; i < s.length(); ++i)
            arr[nRows - 1 - abs(nRows - 1 - (i % nCount))].push_back(s[i]);
        string result;

        for(int i = 0; i < nRows; ++i)
            result.append(arr[i]);

        return result;
}

int main()
{
        string s;
        int nRows;
        while(cin>>s>>nRows)
            cout<<convert(s, nRows)<<endl;
        return 0;
}