Splay hdu3487 Play with Chain

传送门:点击打开链接

题意:有很多次操作。可以讲区间一部分取出来插入到令一个位置,也能翻转区间

思路:翻转区间和添加删除等区间操作,都是splay的最强大的地方,这题也可以说是splay的一道超级经典的入门题

#include<map>
#include<set>
#include<cmath>
#include<ctime>
#include<stack>
#include<queue>
#include<cstdio>
#include<cctype>
#include<string>
#include<vector>
#include<cstring>
#include<iomanip>
#include<iostream>
#include<algorithm>
#include<functional>
#define fuck(x) cout<<"["<<x<<"]"
#define FIN freopen("input.txt","r",stdin)
#define FOUT freopen("output.txt","w+",stdout)
using namespace std;
typedef long long LL;
typedef pair<int, int>PII;


const int MX = 3e5 + 5;
const int mod = 1e9 + 7;
const int INF = 0x3f3f3f3f;


int size[MX];
int num[MX], col[MX], n, m;
int son[MX][2], fa[MX], root, sz;
void Link(int x, int y, int c) {
    fa[x] = y; son[y][c] = x;
}
void push_up(int rt) {
    size[rt] = size[son[rt][0]] + size[son[rt][1]] + 1;
}
void Reverse(int rt){
    col[rt] ^= 1;
    swap(son[rt][0], son[rt][1]);
}
void push_down(int rt) {
    if(col[rt]) {
        Reverse(son[rt][0]);
        Reverse(son[rt][1]);
        col[rt] = 0;
    }
}
void Rotate(int x, int c) {
    int y = fa[x];
    push_down(y); push_down(x);
    Link(x, fa[y], son[fa[y]][1] == y);
    Link(son[x][!c], y, c);
    Link(y, x, !c);
    push_up(y);
}
void Splay(int x, int g) {
    push_down(x);
    while(fa[x] != g) {
        int y = fa[x], cx = son[y][1] == x, cy = son[fa[y]][1] == y;
        if(fa[y] == g) Rotate(x, cx);
        else {
            if(cx == cy) Rotate(y, cy);
            else Rotate(x, cx);
            Rotate(x, cy);
        }
    }
    push_up(x);
    if(!g) root = x;
}
void NewNode(int f, int &rt) {
    rt = ++sz;
    fa[rt] = f, size[rt] = 1;
    son[rt][0] = son[rt][1] = col[rt] = 0;
}
int Select(int k, int g) {
    int rt = root;
    while(size[son[rt][0]] != k) {
        if(size[son[rt][0]] > k) rt = son[rt][0];
        else k -= size[son[rt][0]] + 1, rt = son[rt][1];
        push_down(rt);
    }
    Splay(rt, g);
    return rt;
}
void Build(int l, int r, int &rt, int f) {
    if(l > r) return;
    int m = (l + r) >> 1, t;
    NewNode(f, rt); num[rt] = m;
    Build(l, m - 1, son[rt][0], rt);
    Build(m + 1, r, son[rt][1], rt);
    push_up(rt);
}
void Prepare(int n) {
    sz = 0;
    NewNode(0, root); num[1] = 0;
    NewNode(root, son[root][1]); num[2] = 0;
    Build(1, n, son[2][0], 2);
    Splay(3, 0);
}
void Print(int rt, int &DFN){
    if(!rt) return;
    push_down(rt);
    Print(son[rt][0], DFN);
    if(num[rt]) printf("%d%c", num[rt], ++DFN == n ? '\n' : ' ');
    Print(son[rt][1], DFN);
}
void Flip(int l, int r){
    Select(l - 1, 0);
    Select(r + 1, root);
    Reverse(son[son[root][1]][0]);
}
void Cut(int a, int b, int c){
    Select(a - 1, 0);
    Select(b + 1, root);
    int w = son[son[root][1]][0];
    son[son[root][1]][0] = 0;
    Splay(son[root][1], 0);
    Select(c, 0);
    Select(c + 1, root);
    son[son[root][1]][0] = w;
    Splay(son[root][1], 0);
}


int main(){
    //FIN;
    while(~scanf("%d%d", &n, &m), n != -1){
        Prepare(n);
        while(m--){
            char op[10]; int a, b, c;
            scanf("%s%d%d", op, &a, &b);
            if(op[0] == 'C'){
                scanf("%d", &c);
                Cut(a, b, c);
            }else Flip(a, b);
        }
        int DFN = 0;
        Print(root, DFN);
    }
    return 0;
}


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