如题，大部分按照oiwiki的板子写的

但是insert部分好像出了问题，求帮看看（）

十分感激

#include <iostream>
using namespace std;
int rt, tot, fa[100005], ch[100005][2];
int val[100005], cnt[100005], sz[100005];
int v[100005];
void maintain(int x) {
	sz[x] = sz[ch[x][0]] + sz[ch[x][1]] + cnt[x];
}
bool get(int x) {
	return x == ch[fa[x]][1];
}
void clear(int x) {
	ch[x][0] = ch[x][1] = fa[x] = val[x] = sz[x] = cnt[x] = 0;
}
void rotate(int x) {
	int y = fa[x], z = fa[y], chk = get(x);
	ch[y][chk] = ch[x][chk ^ 1];
	if (ch[x][chk ^ 1]) fa[ch[x][chk ^ 1]] = y;
	ch[x][chk ^ 1] = y;
	fa[y] = x;
	fa[x] = z;
	if (z) ch[z][y == ch[z][1]] = x;
	maintain(y);
	maintain(x);
}
/*void splay(int x) {
	for (int f = fa[x]; f = fa[x], f; rotate(x)) {
		if (fa[f]) rotate(get(x) == get(f) ? f : x);
	}
	rt = x;
}*/
void splay(int x, int goal){
	for (int i; (i = fa[x]) != goal; rotate(x)) {
		if (fa[i] != goal) {
			rotate(get(x) == get(i) ? i : x);
		}
	}
	if (goal == 0) {
		rt = x;
	}
}
void insert(int k) {
	if (!rt) {
		val[++tot] = k;
		cnt[tot]++;
		rt = tot;
		maintain(rt);
		return ;
	}
	int cur = rt, f = 0;
	while (1) {
		if (val[cur] == k) {
			cnt[cur]++;
			maintain(cur);
			maintain(f);
			rotate(cur);
			break;
		}
		f = cur;
		cur = ch[cur][val[cur] < k];
		if (!cur) {
			val[++tot] = k;
			cnt[tot]++;
			fa[tot] = f;
			ch[f][val[f] < k] = tot;
			maintain(tot);
			maintain(f);
			rotate(tot);
			break;
		}
	}
}
int find(int k) {
  int cur = rt;
  while (1) {
    if (ch[cur][0] && k <= sz[ch[cur][0]]) {
      cur = ch[cur][0];
    } else {
      k -= cnt[cur] + sz[ch[cur][0]];
      if (k <= 0) {
        rotate(cur);
        return val[cur];
      }
      cur = ch[cur][1];
    }
  }
}
void dfs(int rt) {
	if (v[rt]) {
		cout << rt << " ";
		return ;
	}
	v[rt] = 1;
	if (rt == 0) {
		return ;
	}
	if (ch[rt][0]) dfs(ch[rt][0]);
	if (ch[rt][1]) dfs(ch[rt][1]);
	cout << rt << " ";
}
int main() {
	int m, n;
	ios::sync_with_stdio(false);
	cin.tie(0); cout.tie(0);
	cin >> n >> m;
	for (int i = 1; i <= n; i++) {
		insert(i);
	}
	while (m--) {
		int x, y;
		cin >> x >> y;
		splay(find(x), 0);
		splay(find(y + 2), find(x));
	}
	dfs(rt);
	return 0; 
}