# 6 ZigZag Conversion – Easy

### Problem:

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”.

### Thoughts:

Use a delta flag to indicate whether next move should go up or go down.

### Solutions:

``````public class Solution {
public String convert(String s, int nRows) {
String[] helper = new String[nRows];
for (int i = 0; i < nRows; i ++){
helper[i] = "";
}
int row = 0;
int delta = 1;
for (int i = 0; i < s.length(); i ++){
char c = s.charAt(i);
helper[row] += c;
if (row == nRows - 1){
delta = -1;
}
else if (row == 0){
delta = 1;
}
row = row + delta;
row = Math.max(0, row);
}//for
String result = "";
for (int i = 0; i < nRows && s.length() > 0; i ++){
result += helper[i];
}
return result;
}
}
``````