记录编号	602282	评测结果	AAAAAAAAAA
题目名称	4166.遵循指令之意	最终得分	100
用户昵称	LikableP	是否通过	通过
代码语言	C++	运行时间	1.677 s
提交时间	2025-07-03 14:39:23	内存使用	8.32 MiB

#include <algorithm>
#include <cstdio>
#include <cstring>

template <typename T> T read();
template <typename T> void write(T, char);
void work(int[], int, int &);

const int MAXN = 1e6 + 10;
int n;
int arr[MAXN], a[MAXN >> 1], b[MAXN >> 1], acnt, bcnt, cnt;
int ansarr, ansa, ansb;

int main() {
  freopen("sort.in", "r", stdin);
  freopen("sort.out", "w", stdout);
  n = read<int>();
  for (int i = 1; i <= n; ++i) {
    arr[i] = read<int>();
    if (i & 1) a[++acnt] = arr[i];
    if (!(i & 1)) b[++bcnt] = arr[i];
  }

  work(arr, n, ansarr);
  work(a, acnt, ansa);
  work(b, bcnt, ansb);

  ::std::sort(a + 1, a + acnt + 1);
  ::std::sort(b + 1, b + bcnt + 1);

  for (int i = 1; i <= bcnt; ++i) {
    arr[++cnt] = a[i];
    arr[++cnt] = b[i];
  }
  if (acnt > bcnt) arr[++cnt] = a[acnt];

  // printf("%d %d %d\n", ansarr, ansa, ansb);
  if ((ansa & 1) != (ansb & 1)) ::std::swap(arr[cnt], arr[cnt - 2]);

  for (int i = 1; i <= cnt; ++i) {
    write(arr[i], " \n"[i == cnt]);
  }
  return 0;
}

int tree[MAXN];
void add(int x, int y) {
  for (; x <= MAXN - 10; x += (x & -x)) tree[x] += y;
}
int ask(int x) {
  int res = 0;
  for (; x; x -= (x & -x)) res += tree[x];
  return res;
}
void work(int arr[], int len, int &ans) {
  memset(tree, 0, sizeof tree);
  ans = 0;
  for (int i = len; i >= 1; --i) {
    ans += ask(arr[i] - 1);
    add(arr[i], 1);
  }
}

#define isdigit(ch) (ch >= '0' && ch <= '9')
template <typename T> T read() {
  T res = 0, f = 1;
  char ch = getchar();
  for (; !isdigit(ch); ch = getchar())
    if (ch == '-') f = -1;
  for (; isdigit(ch); ch = getchar()) res = (res << 3) + (res << 1) + (ch ^ 48);
  return res * f;
}

template <typename T> void write(T x, char ed) {
  if (x < 0) x = -x, putchar('-');
  static int sta[sizeof(T) << 2], top = 0;
  do {
    sta[++top] = x % 10;
    x /= 10;
  } while (x);
  while (top) {
    putchar(sta[top--] ^ 48);
  }
  putchar(ed);
}