Simplest ways without reverse() is : -

import java.io.; import java.util.;

public class Solution {

public static void main(String[] args) {

    Scanner sc=new Scanner(System.in);
    String str=sc.next();
    /* Enter your code here. Print output to STDOUT. */
    String rev="";
    for(int i=str.length()-1;i>=0;i--){
        rev+=str.charAt(i);
    }
    if(rev.equals(str)){
        System.out.println("Yes");
    }
    else{
        System.out.println("No");
    }
}

}