Juanzhang

#include <bits/stdc++.h>
using namespace std;

const int maxn = 1e5 + 10;
int n, k, a[maxn];

struct persistent_trie {
  static const int maxsz = maxn * 32;
  int tot, rt[maxn], sz[maxsz], tid[maxsz], ch[2][maxsz];
  void ins(int& k, int rt, int id, int x, int now) {
    sz[k = ++tot] = sz[rt] + 1;
    ch[0][k] = ch[0][rt], ch[1][k] = ch[1][rt];
    if (now == -1) {
      tid[k] = id; return;
    }
    int chk = x >> now & 1;
    ins(ch[chk][k], ch[chk][rt], id, x, now - 1);
  }
  inline void build() {
    for (int i = 1; i <= n; i++) {
      ins(rt[i], rt[i - 1], i, a[i], 30);
    }
  }
  inline int query(int l, int r, int x) {
    int p = rt[l - 1], q = rt[r];
    for (int i = 30; ~i; i--) {
      int tmp = x >> i & 1, chk = sz[ch[tmp][q]] - sz[ch[tmp][p]] ? tmp : tmp ^ 1;
      p = ch[chk][p], q = ch[chk][q];
    }
    return tid[q];
  }
} trie;

struct node {
  int st, l, r, pos;
  node(int _s = 0, int _l = 0, int _r = 0) :
    st(_s), l(_l), r(_r), pos(trie.query(l, r, a[st])) {}
  inline int get_val() const {
    return a[pos] ^ a[st];
  }
  inline bool operator < (const node& o) const {
    return get_val() > o.get_val();
  }
};

priority_queue <node> Q;

int main() {
  scanf("%d %d", &n, &k);
  for (int i = 1; i <= n; i++) {
    scanf("%d", a + i);
  }
  trie.build();
  for (int i = 1; i < n; i++) {
    Q.push(node(i, i + 1, n));
  }
  while (k--) {
    node p = Q.top();
    printf("%d ", p.get_val()), Q.pop();
    if (p.l < p.pos) Q.push(node(p.st, p.l, p.pos - 1));
    if (p.pos < p.r) Q.push(node(p.st, p.pos + 1, p.r));
  }
  return 0;
}