题目描述
仅供参考
样例
import java.io.BufferedReader;
import java.io.IOException;
import java.io.InputStreamReader;
import java.util.Arrays;
import java.util.HashSet;
import java.util.Set;
public class Main {
public static void main(String[] args) throws IOException {
BufferedReader br = new BufferedReader(new InputStreamReader(System.in));
int n = Integer.parseInt(br.readLine());
int[] arr = new int[n + 1];
Set<Integer> set = new HashSet<>();
String[] s = br.readLine().split(" ");
int cnt = 0;
for (int i = 1; i <= n; i++) {
int cur = Integer.parseInt(s[i - 1]);
if (!set.contains(cur)) {
arr[cnt++] = cur;
set.add(cur);
}
}
Arrays.sort(arr);
System.out.println(set.size());
for (int i = n - set.size() + 1; i <= n; i++) {
System.out.print(arr[i] + " ");
}
}
}