Все работает, но последнее условие не проходит.
package com.javarush.task.jdk13.task06.task0634;
import java.io.BufferedReader;
import java.io.BufferedWriter;
import java.io.InputStreamReader;
import java.lang.reflect.Array;
import java.util.Scanner;
/*
Шахматная доска
*/
public class Solution {
public static char[][] array;
public static void main(String[] args) throws Exception {
BufferedReader reader = new BufferedReader(new InputStreamReader(System.in));
int a = Integer.parseInt(reader.readLine());
array = new char[a][a];
for (int i = 0; i < array.length; i++) {
for (int j = 0; j < array.length; j++) {
if(i%2==0&&j%2==0||i%2!=0&&j%2!=0){
array[i][j]='#';
}
if(i%2==0&&j%2!=0||i%2!=0&&j%2==0) {
array[i][j] = ' ';
}
}
}
for (int i = 0; i < array.length; i++) {
for (int j = 0; j < array[i].length; j++) {
System.out.print(array[i][j]);
}
System.out.println(" ");
}
}
}
