java根据输入的数组内容判断是否有重复

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

/* Name of the class has to be "Main" only if the class is public. */
class Ideone
{
    static boolean foo(String[] arr)
    {
        for (int k = 0; k < arr.length; k++)
            for (int i = 0; i < arr[0].length() - 1; i++)
                for (int j = i + 1; j < arr[0].length(); j++)
                {
                    if (arr[k].charAt(i) == arr[k].charAt(j)) return true;
                }
        for (int k = 0; k < arr[0].length(); k++)
            for (int i = 0; i < arr.length - 1; i++)
                for (int j = i + 1; j < arr.length; j++)
                    if (arr[i].charAt(k) == arr[j].charAt(k)) return true;
        return false;
    }

    public static void main (String[] args) throws java.lang.Exception
    {
        // your code goes here
        String[] arr = new String[3];
        arr[0] = "321";
        arr[1] = "132";
        arr[2] = "212";
        boolean b = foo(arr);
        System.out.println(b);
    }
}