Palindrome-checks Letters and numbers, ignores other signs

import java.util.Scanner;

public class palindrome {
    public static void main(String[] args) {
        System.out.println("No of Inputs:");
        Scanner sc=new Scanner(System.in);
        int noIn=sc.nextInt();
        System.out.println("Enter the Inputs");
        String[] inSt= new String[noIn];
        String [] result=new String[noIn];
        String temp=sc.nextLine();
        for(int i=0;i<noIn;i++){
           inSt[i]=sc.nextLine().toUpperCase();
           char[] inCh =inSt[i].toCharArray();
           result[i]=istPalindrom(inCh);

        }
        for(String i:result){

        System.out.print(i+"\t");
        }
        System.out.println();
    }

    public static String istPalindrom(char[] wort){
        int k=0;
        for(int j=0;j<wort.length;j++){
            if((int)wort[j]>64&& (int)wort[j]<91||(int)wort[j]>47&& (int)wort[j]<58){
                wort[k]=wort[j];
                k++;
            }
        }
        String palindrom = "N";
            for(int i = 0; i <=k/2-1; i++){

                if(wort[i] != wort[k-i-1]){
                   palindrom="N";
                }else{
                    palindrom = "Y";
                }
            }

        return palindrom;
    }
}