What went wrong in the following code to reverse given numbers?

/* package codechef; // don’t place package name! */

import java.util.;
import java.lang.
;
import java.io.*;

/* Name of the class has to be “Main” only if the class is public. */
class Codechef
{
public static void main (String[] args) throws java.lang.Exception
{
// your code goes here
try(BufferedReader br = new BufferedReader(new InputStreamReader(System.in))){
String count = br.readLine();
String sarr[] = new String[Integer.valueOf(count)];
for(int i=0;i<sarr.length;i++){
sarr[i] = br.readLine();
}
for(int i=0;i<sarr.length;i++){
char carr[] = sarr[i].toCharArray();
StringBuilder sb = new StringBuilder();
for(int j=carr.length-1; j>=0; j–){
sb.append(carr[j]);
}
System.out.println(sb);
}
} catch(IOException ex){
System.out.println(ex);
}
}
}