public class stringbuilder {

public static void main(String[] args) {

StringBuilder sb = new StringBuilder("rohan");

for (int i = 0; i < sb.length()/2; i++) {

int front = i;

int back = sb.length() - 1 - i;

char frontChar = sb.charAt(front);

char backChar = sb.charAt(back);

sb.setCharAt(front, backChar);

sb.setCharAt(back, frontChar);

}

System.out.println(sb);

}

}