1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
| public class ZigZagConversion {
public String convert(String s, int numRows) {
if (numRows <= 0) {
return null;
}
if (s == null || s.isEmpty() || s.length() <= numRows || numRows == 1) {
return s;
}
int size = 2 * numRows - 2;
StringBuilder sb = new StringBuilder();
for (int i = 0; i < numRows; i++) {
for (int j = i; j < s.length(); j += size) {
sb.append(s.charAt(j));
if (i != 0 && i != numRows - 1) {
int index = j + size - 2 * i;
if (index < s.length()) {
sb.append(s.charAt(index));
}
}
}
}
return sb.toString();
}
}
|