LeetCode 6. ZigZag Conversion 详细解析

这张图片是对ZigZag的描述和程序的核心思想
/************************************************************************
*
* 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”.
*
*
************************************************************************/

#include 
#include 
#include 
using namespace std;

string convert(string s, int nRows) {
    //The cases no need to do anything
    if (nRows<=1 || nRows>=s.size()) return s;

    vector<string> r(nRows);
    int row = 0;
    int step = 1;
    for(int i=0; iif (row == nRows-1) step = -1;
        if (row == 0) step = 1;
        //cout << row <
        r[row] += s[i];
        row += step;
    }

    string result;
    for (int i=0; ireturn result;
}

int main(int argc, char**argv){

    string s;
    int r;

    s = "PAYPALISHIRING";
    r = 5;
    cout << s << " : " << convert(s, r) << endl;

}