Вроде все четко, что не так ?
package com.javarush.task.pro.task03.task0305;
import java.util.Scanner;
/*
Три числа
*/
public class Solution {
public static void main(String[] args) {
//напишите тут ваш код
Scanner scanner = new Scanner(System.in);
int a = scanner.nextInt(), b = scanner.nextInt(), c = scanner.nextInt();
boolean q = (a == b), w = (a == c), e = (b == c), r = ((a == b) && (b == c));
if (r) {
System.out.println(a + " " + b + "" + c);
} else if (w) {
System.out.println(a + " " + c);
} else if (e) {
System.out.println(b + " " + c);
} else if (q) {
System.out.println(a + " " + b);
}
}
}