zigzeg.cpp

//
//  zigzeg.cpp
//  
//
//  Created by Ally Wang on 12/17/14.
//
//

#include <stdio.h>
#include <iostream>
#include <vector>
#include <string>
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; i<s.size(); i ++) {
        if (row == nRows-1) step = -1;
        if (row == 0) step = 1;
        //cout << row <<endl;
        r[row] += s[i];
        row += step;
    }
    string result;
    for (int i=0; i<nRows; i++){
        result += r[i];
    }
    return result;
}
int main(int argc, char**argv){
    string s;
    int r;
    s = "abcdefghijklmn";
    r = 3;
    cout << s << " : " << convert(s, 4) << endl;
    cout << s << " : " << convert(s, 5) <<endl;

}