Problem 2 线段树

$des$

一个无限长的 01 序列，初始全为 0，每次选择一个区间 [l,r] 进行操作，有三种操作：
1. l r 将 [l,r] 中所有元素变成 1。
2. l r 将 [l,r] 中所有元素变成 0。
3. l r 将 [l,r] 中所有元素异或上 1。
每次操作后询问最左边的 0 在哪个位置.

$sol$

线段树

将所有可能成为答案的点加入线段树的根节点维护

$code$

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

using namespace std;

#define LL long long
#define Rep(i, a, b) for(int i = a; i <= b; i ++)
#define gc getchar()

inline LL read() {
    LL x = ; char c = gc;
    while(c < '' || c > '') c = gc;
    while(c >= '' && c <= '') x = x *  + c - '', c = gc;
    return x;
}

const int N = 1e5 + , M = N *  * ;

struct Node {
    LL opt, l, r;
} Ask[N];
LL A[M], js;
int n;

struct Node_ {
    int Cnt[][M << ], Size[M << ], F[M << ];

    #define lson jd << 1
    #define rson jd << 1 | 1

    void Build_tree(int l, int r, int jd) {
        F[jd] = -;
        Size[jd] = r - l + ;
        Cnt[][jd] = Size[jd];
        if(l == r) return ;
        int mid = (l + r) >> ;
        Build_tree(l, mid, lson), Build_tree(mid + , r, rson);
    }

    void Push_down(int jd) {
        int f = F[jd];
        if(f == ) {
            F[lson] = F[rson] = ;
            Cnt[][lson] = Size[lson], Cnt[][rson] = Size[rson];
            Cnt[][lson] = , Cnt[][rson] = ;
            F[jd] = -;
        } else if(f == ) {
            F[lson] = F[rson] = ;
            Cnt[][lson] = Size[lson], Cnt[][rson] = Size[rson];
            Cnt[][lson] = , Cnt[][rson] = ;
            F[jd] = -;
        } else {
            if(F[lson] == ) {
                swap(Cnt[][lson], Cnt[][lson]);
                F[lson] = -;
            } else {
                if(F[lson] == -) {
                    F[lson] = ;
                    swap(Cnt[][lson], Cnt[][lson]);
                } else if(F[lson] == ) {
                    F[lson] = ;
                    Cnt[][lson] = Size[lson], Cnt[][lson] = ;
                } else {
                    F[lson] = ;
                    Cnt[][lson] = Size[lson], Cnt[][lson] = ;
                }
            }
            if(F[rson] == ) {
                swap(Cnt[][rson], Cnt[][rson]);
                F[rson] = -;
            } else {
                if(F[rson] == -) {
                    F[rson] = ;
                    swap(Cnt[][rson], Cnt[][rson]);
                } else if(F[rson] == ) {
                    F[rson] = ;
                    Cnt[][rson] = Size[rson], Cnt[][rson] = ;
                } else {
                    F[rson] = ;
                    Cnt[][rson] = Size[rson], Cnt[][rson] = ;
                }
            }
            F[jd] = -;
        }
    }

    void Sec_G(int l, int r, int jd, int x, int y, int num){
        if(x <= l && r <= y) {
            Cnt[num][jd] = Size[jd];
            Cnt[num ^ ][jd] = ;
            F[jd] = num;
//            cout << Cnt[1][jd] << " " << Cnt[0][jd] << "\n";
            return ;
        }
        if(F[jd] != -) Push_down(jd);
        int mid = (l + r) >> ;
//        cout << Cnt[0][lson] << "\n";
        if(x <= mid) Sec_G(l, mid, lson, x, y, num);
        if(y > mid)  Sec_G(mid + , r, rson, x, y, num);
        Cnt[][jd] = Cnt[][lson] + Cnt[][rson];
        Cnt[][jd] = Cnt[][lson] + Cnt[][rson];
    }

    int Ask(int l, int r, int jd) {
        if(l == r) {
            return l;
        }
        if(F[jd] != -) Push_down(jd);
        int mid = (l + r) >> ;
//        cout << Cnt[0][lson] << "\n";
        if(Cnt[][lson]) return Ask(l, mid, lson);
        else return Ask(mid + , r, rson);
    }

    void Seg_fz(int l, int r, int jd, int x, int y) {
        if(x <= l && r <= y) {
            if(F[jd] == -) {
                swap(Cnt[][jd], Cnt[][jd]);
                F[jd] = ;
                return ;
            } else if(F[jd] == ) {
                F[jd] = ;
                Cnt[][jd] = Size[jd];
                Cnt[][jd] = ;
            } else if(F[jd] == ) {
                F[jd] = ;
                Cnt[][jd] = ;
                Cnt[][jd] = Size[jd];
            } else {
                F[jd] = -;
                swap(Cnt[][jd], Cnt[][jd]);
            }
            return ;
        }
        if(F[jd] != -) Push_down(jd);
        int mid = (l + r) >> ;
//        cout << Cnt[0][lson] << "\n";
        if(x <= mid) Seg_fz(l, mid, lson, x, y);
        if(y > mid)  Seg_fz(mid + , r, rson, x, y);
        Cnt[][jd] = Cnt[][lson] + Cnt[][rson];
        Cnt[][jd] = Cnt[][lson] + Cnt[][rson];
    }
} Segtree;

inline LL Getans() {
    int w = Segtree.Ask(, js, );
//    if(A[w - 1] + 1 != A[w]) return A[w - 1] + 1;
//    else return A[w];
    return A[w];
}

int main() {
    freopen("a.in", "r", stdin);
    freopen("a.out", "w", stdout);
    n = read();
    Rep(i, , n) {
        LL opt = read(), l = read(), r = read();
        A[++ js] = l, A[++ js] = r; A[++ js] = max(1ll, l - ), A[++ js] = r + ;
        Ask[i] = (Node) {
            opt, l, r
        };
    }
    A[++ js] = ;
    sort(A + , A + js + );
    js = unique(A + , A + js + ) - A - ;
    Segtree.Build_tree(, js, );
//    Rep(i, 1, 10) cout << Segtree.F[i] << " ";
//    return 0;
    Rep(i, , n) {
        LL opt = Ask[i].opt, l = Ask[i].l, r = Ask[i].r;
        int wl = lower_bound(A + , A + js + , l) - A;
        int wr = lower_bound(A + , A + js + , r) - A;
        if(opt == ) {
            Segtree.Sec_G(, js, , wl, wr, );
            cout << Getans() << "\n";
        } else if(opt == ) {
            Segtree.Sec_G(, js, , wl, wr, );
            cout << Getans() << "\n";
        } else {
            Segtree.Seg_fz(, js, , wl, wr);
            cout << Getans() << "\n";
        }
    }

    return ;
}