【模板】文艺平衡树

如题，是一个模板。。。

Splay：

#include <algorithm>
#include <iostream>
#include <cstring>
#include <cstdio>
#include <cctype>

inline void read(int & x)
{
    x = 0;
    int k = 1;
    char c = getchar();
    while (!isdigit(c))
        if (c == '-') c = getchar(), k = -1;
        else c = getchar();
    while (isdigit(c))
        x = (x << 1) + (x << 3) + (c ^ 48),
        c = getchar();
    x *= k;
}

const int MAXN = 101015;
int n, m, x, y;

int a[101010];

struct SplayHello
{
    int rt = 0, tot = 0;
    int cnt[MAXN];
    int siz[MAXN];
    int tag[MAXN];
    int val[MAXN]; 
    int faz[MAXN];
    int son[MAXN][2];
    
    int Getson(int u)
    {
        return son[faz[u]][1] == u;
    }
    
    void Update(int u)
    {
        siz[u] = siz[son[u][0]] + siz[son[u][1]] + cnt[u];
    }
    
    void Pushdown(int u)  //ok
    {
        if (!tag[u] || !u) return;
        if (son[u][0]) tag[son[u][0]] ^= 1;
        if (son[u][1]) tag[son[u][1]] ^= 1;
        son[u][0] ^= son[u][1],
        son[u][1] ^= son[u][0],
        son[u][0] ^= son[u][1];
        tag[u] = 0;
    }
    
    int Build(int dad, int l, int r)  //ok
    {
        if (l > r) return 0;
        int mid = (l + r) >> 1;
        int now = ++tot;
        tag[now] = 0;
        faz[now] = dad;
        val[now] = a[mid];
        cnt[now] = siz[now] = 1;
        son[now][0] = Build(now, l, mid - 1);
        son[now][1] = Build(now, mid + 1, r);
        //²»ÄÜÓÃtotµ±¸¸Ç×£¬»á¸Ä±ä 
        Update(now);
        return now;
    }
    
    void Rotate(int u)   //ok
    {
        int y = faz[u], z = faz[y], ch = Getson(u);
        Pushdown(y), Pushdown(u);
        int b = son[u][ch ^ 1];
        int d = Getson(y);
        son[u][ch ^ 1] = y, son[y][ch] = b;
        faz[y] = u, faz[b] = y, faz[u] = z;
        if (z) son[z][d] = u;
        Update(y), Update(u);
    }
    
    void Splay(int u, int tar)  //ok
    {
        while (faz[u] != tar)
        {
            if (faz[faz[u]] != tar)
                if (Getson(u) == Getson(faz[u])) Rotate(faz[u]);
                else Rotate(u);
            Rotate(u);
        }
        if (!tar) rt = u;
    }
    
    int GetKth(int k)
    {
        int now = rt;
        while (true)
        {
            Pushdown(now);
            if (siz[son[now][0]] >= k) now = son[now][0];
            else if (siz[son[now][0]] + cnt[now] >= k) return now;
            else k -= siz[son[now][0]] + cnt[now], now = son[now][1];
        }
    }
    
    void Rever(int l, int r)
    {
        int L = GetKth(l - 1);
        int R = GetKth(r + 2);
        Splay(L, 0); Splay(R, L);
        tag[son[son[rt][1]][0]] ^= 1;
        Update(L), Update(R), Update(son[R][0]);
    }
    
    void print(int u)
    {
        Pushdown(u);
        if (son[u][0]) print(son[u][0]);
        if (val[u] != -2147483600 && val[u] != 2147483600) 
            printf("%d ", val[u]);
        if (son[u][1]) print(son[u][1]);
    }
    
    void BuildT(int l, int r)
    {
        rt = Build(0, l, r);
    }
    
    void printT()
    {
        print(rt);
    }
}splay;

signed main()
{
    read(n), read(m);
    for (int i = 1; i <= n; ++i) a[i] = i;
    a[n + 1] = 2147483600;
    a[0] = -2147483600;
    splay.BuildT(0, n + 1);
    for (int i = 1; i <= m; ++i)
    {
        read(x), read(y);
        splay.Rever(x, y);
    }
    splay.printT();
    return 0;
}

FHQ：：

#include <algorithm>
#include <iostream>
#include <cstring>
#include <cstdio>
#include <cctype>

inline void read(int & x)
{
    x = 0;
    int k = 1;
    char c = getchar();
    while (!isdigit(c))
        if (c == '-') c = getchar(), k = -1;
        else c = getchar();
    while (isdigit(c))
        x = (x << 1) + (x << 3) + (c ^ 48),
        c = getchar();
    x *= k;
}

const int MAXN = 1e5 + 999;
int seed = 1024, n, m, l, r, rt = 0, tot = 0, rnd[MAXN], tag[MAXN], val[MAXN], siz[MAXN], son[MAXN][2]; 

inline int Rand(void)
{
    return seed = (int)seed * 462711LL % 2147483647;
}

inline int New(int x)
{
    ++tot;
    siz[tot] = 1;
    val[tot] = x;
    rnd[tot] = Rand();
    tag[tot] = son[tot][1] = son[tot][0] = 0;
    return tot;    
}

inline void Swap(int &a, int &b) 
{
    a ^= b, b ^= a, a ^= b;
}

inline void Pushup(int u)
{
    siz[u] = siz[son[u][0]] + siz[son[u][1]] + 1;
}

inline void Pushdown(int u)
{
    if (!tag[u]) return;
    tag[son[u][0]] ^= 1;
    tag[son[u][1]] ^= 1;
    Swap(son[u][0], son[u][1]);
    tag[u] = 0;
}

inline void Split(int u, int k, int &a, int &b)
{
    if (!u) { a = b = 0; return; }
    Pushdown(u);
    if (k <= siz[son[u][0]]) b = u, Split(son[u][0], k, a, son[b][0]);
    else a = u, Split(son[u][1], k - siz[son[u][0]] - 1, son[a][1], b);
    Pushup(u);
}

inline void Merge(int & u, int a, int b)
{
    if (!a || !b) { u = a | b; return; } 
    if (rnd[a] < rnd[b]) u = a, Pushdown(a), Merge(son[u][1], son[a][1], b), Pushup(a);
    else u = b, Pushdown(b), Merge(son[u][0], a, son[b][0]), Pushup(b);
}

inline void Insert(int x)
{
    int u = New(x);
    Merge(rt, rt, u);
}

inline void Print(int u)
{
    if (!u) return;
    Pushdown(u);
    Print(son[u][0]);
    printf("%d ", val[u]);
    Print(son[u][1]);
}

int a, b, c;

signed main()
{
    read(n), read(m);
    for (int i = 1; i <= n; ++i) Insert(i);
    for (int i = 1; i <= m; ++i)
    {
        a = b = c = 0;
        read(l), read(r);
        Split(rt, r, a, b);
        Split(a, l - 1, a, c);
        tag[c] ^= 1;
        Merge(a, a, c);
        Merge(rt, a, b);
    }
    Print(rt);
    return 0;
}