平衡树裸题，这是新的平衡树模板。

平衡树，区间加值，区间翻转，区间查询最小值。

要时刻记住维护标记哦~

WA了好几次，对拍了一百多组数据，发现有两个操作没有更新信息。
我还是太年轻了。。。too young too simple。。。

#include<map>
#include<queue>
#include<stack>
#include<utility>
#include<string>
#include<cstdio>
#include<cstdlib>
#include<cstring>
#include<ctime>
#include<cmath>
#include<iostream>
#include<algorithm>
#define Mp(x,y) std::make_pair(x,y)
#define L(x)   b[x].c[0]
#define R(x)   b[x].c[1]
#define Fa(x)  b[x].fa
#define Clear(x) b[x] = emp

const int MAXN = 100005, SIZE = 200005 , INF = (1LL<<31)-1;

int n , m;
int a[MAXN] = {0};
struct TreeNode
{
    int c[2],fa,cnt;
    int min,val;
    int add,rev;
}b[SIZE] = {0}, emp = {0};
int root, size , blen;

int NewNode(int val)
{
    ++blen, b[blen]t = 1;
    b[blen].min = b[blen].val = val;
    return blen;
}
void PushDown(int x)
{
    if(b[x].rev)
    {
        std::swap(L(x),R(x));
        if(L(x)) b[L(x)].rev ^= 1;
        if(R(x)) b[R(x)].rev ^= 1;
        b[x].rev = 0;
    }
    if(b[x].add)
    {
        if(L(x)) b[L(x)].add += b[x].add, b[L(x)].val += b[x].add, b[L(x)].min += b[x].add;
        if(R(x)) b[R(x)].add += b[x].add, b[R(x)].val += b[x].add, b[R(x)].min += b[x].add;
        b[x].add = 0;
    }
}
void Update(int x)
{
    b[x]t = b[L(x)]t + b[R(x)]t + 1 , b[x].min = b[x].val;
    if(L(x)) b[x].min = std::min(b[x].min,b[L(x)].min);
    if(R(x)) b[x].min = std::min(b[x].min,b[R(x)].min);
}
void Rotate(int x,int &k)
{
    int y = Fa(x) , z = Fa(y);

    PushDown(y), PushDown(x);

    int i = (R(y) == x) ,j = i^1 , fi = (R(z) == y);

    if(y != k) b[z].c[fi] = x;else  k = x;

    Fa(x) = z,Fa(y) = x ,Fa(b[x].c[j]) = y;
    b[y].c[i] = b[x].c[j], b[x].c[j] = y ;

    Update(y), Update(x);
}
void Splay(int x,int &k)
{
    PushDown(x);
    while(x != k)
    {
        int y = Fa(x), z = Fa(y);
        if(y != k)
        {
            if((y==R(z))^(x==R(y)))Rotate(x,k);
            else   Rotate(y,k);
        }
        Rotate(x,k);
    }
    Update(x);
    return;
}
int Find(int p)
{
    int pos = root;

    while(1)
    {
        PushDown(pos);
        int lc = b[L(pos)]t + 1;
        if(p == lc) break;
        else if(p < lc) pos = L(pos);
        else { p -= lc ,pos = R(pos);}
    }
    return pos;
}
int GetInveral(int l,int r)
{
    if(l == 1 && r == size)
      return root;
    else if(l == 1)
    {
     Splay(Find(r+1),root);
     return L(root);    
    }
    else if(r == size)
    {
     Splay(Find(l-1),root);
     return R(root);    
    }
    else
    {
     Splay(Find(l-1),root);
     Splay(Find(r+1),R(root));
     return L(R(root));
    }
}

void Insert(int x,int p)
{
    int pos = NewNode(p);

    if(!size)   root = pos;
    else
    {   
      Splay(Find(x),root);

      if(x == size)
      {
        R(root) = pos, Fa(pos) = root;
        Update(root);
      }
      else
      {
        Splay(Find(x+1),R(root));
        L(R(root)) = pos ,Fa(pos) = R(root);
        Update(Fa(pos)), Update(root);
      }
    }
    size ++;
}
void Del(int x)
{
    int pos = Find(x);
    Splay(pos,root);

    if(size == 1) root = 0;
    else
    {
      int y;

      if(x == size) y = L(root);
      else
      {
        Splay(Find(x+1),R(root));
        y = R(root);
        L(y) = L(root) ,Fa(L(y)) = y;
      }
       Fa(y) = 0,root = y, Update(root);
    }
    Clear(pos);

    size--;
}
void Add(int l,int r,int p)
{ 
    int pos = GetInveral(l,r);

    b[pos].val += p; 
    b[pos].min += p; 
    b[pos].add += p;

    while(pos != root)
    { 
      Update(Fa(pos));
      pos = Fa(pos);
    }
}
void Reverse(int l,int r)
{
    int pos = GetInveral(l,r);
    b[pos].rev ^= 1;
}
void Revolve(int l,int r,int T)
{
    int len = r-l+1;
    T = ((T%len)+len)%len;

    if(!T) return;
    Reverse(l,r-T);
    Reverse(r-T+1,r);
    Reverse(l,r);
}
int GetMin(int l,int r)
{
    int pos = GetInveral(l,r);
    return b[pos].min;
}
int BuildTree(int ll,int rr,int fa)
{
    int ret = (ll + rr)>>1;

    b[ret].fa = fa , b[ret].val = a[ret];
    if(ll < ret) b[ret].c[0] = BuildTree(ll,ret-1,ret);
    if(ret < rr) b[ret].c[1] = BuildTree(ret+1,rr,ret);
    Update(ret);

    return ret;
}
int read()
{
    int x = 0, f = 1;char c = getchar();
    while(c < '0' || c > '9') {if(c == '-')f = -1; c = getchar();}
    while(c >= '0' && c <= '9'){x = (x<<3) + (x<<1) + (c-'0'); c = getchar();}
    return x * f;
}
void write(int x)
{
    if(x < 0) putchar('-'),x = -x;
    static char s[10];int sl = 0;
    while(x) s[++sl] = x%10 + '0',x /= 10;
    if(!sl) {putchar('0');return;}
    while(sl) putchar(s[sl--]);
}
int main()
{
#ifndef ONLINE_JUDGE
    freopen("poj3580.in","r",stdin);
    freopen("poj3580.out","w",stdout);
#endif

    n = read();
    for(int i = 1; i<= n; i++)
        a[i] = read();

    root = BuildTree(1,n,0);
    blen = size = n;

    m = read();
    while(m--)
    {
        char s[10];int a, b, c;
        scanf("%s",s);

        switch(s[0])
        {
            case 'D':a = read();
                    Del(a);
                    break;
            case 'I':a = read(), b = read();
                    Insert(a, b);
                    break;
            case 'A':a = read(), b = read(), c = read();
                    Add(a, b, c);
                    break;
            case 'M':a = read(), b = read();
                    write(GetMin(a, b));puts("");
                    break;
            case 'R':
                switch(s[3])
                {
                 case 'E':a = read(), b = read();
                        Reverse(a, b);
                        break;
                 case 'O':a = read(), b = read(), c = read();
                        Revolve(a, b, c);
                        break;
                }
                break;
        }
    }

#ifndef ONLINE_JUDGE
    fclose(stdin);
    fclose(stdout);
#endif
    return 0;
}

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