Find 2 missing numbers in an array of integers with two missing values

Question

How do you do this? The values are unsorted but are of [1..n] Example array [3,1,2,5,7,8]. Answer: 4, 6

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Answer 1

public class MissingNumber{

static int[] array = { 1, 3, 5 };

public static void getMissingNumber() {

for (int i = 0; i < array.length; i++)
    System.out.println(array[i] + " ");

System.out.println("The Missing Number is:");
 int j = 0;
for (int i = 1; i <= 5; i++) {
    if (j < array.length && i == array[j])
    j++;
    else
    System.out.println(i + " ");
}

}
public static void main(String[] args) {
getMissingNumber();
}

}