UOJ#191. 【集訓隊互測2016】Unknown

傳送門
這個題目實際上能夠創建出樹,而後重鏈剖分維護一條鏈的凸包
而後離線詢問排序斜率作到 \(nlog^2n\),或者點分治+平衡樹也行
可是這個題目卡空間,數組一不當心就爆了卡一卡也能過
考慮其它空間常數小而且又好寫的作法
根據通常的二進制分組的方法,每次這個塊滿了就合併兒子的凸包
這樣顯然不對,只要又刪又加就假了
咱們換一種方法,每次這個塊滿了就合併線段樹同一層前一個節點的兒子的凸包
這樣每次都要花費 \(len\) 次添加操做才能換來一次 \(2len\) 的合併
此時的沒有合併節點頂多 \(2log\)
查詢就定位每一個節點,在凸包上二分便可
時間 \(nlog^2n\) 空間 \(nlogn\)c++

# include <bits/stdc++.h>
using namespace std;
typedef long long ll;

namespace IO {
    const int maxn(1 << 21 | 1);

    char ibuf[maxn], *iS, *iT, c;
    int f;
    
    inline char Getc() {
        return iS == iT ? (iT = (iS = ibuf) + fread(ibuf, 1, maxn, stdin), (iS == iT ? EOF : *iS++)) : *iS++;
    }

    template <class Int> inline void In(Int &x) {
        for (c = Getc(), f = 1; c < '0' || c > '9'; c = Getc()) f = c == '-' ? -1 : 1;
        for (x = 0; c >= '0' && c <= '9'; c = Getc()) x = (x << 1) + (x << 3) + (c ^ 48);
        x *= f;
    }
}

using IO :: In;

const int maxn(1 << 20 | 1);
const int mod(998244353);
const ll inf(1e18);

struct Point {
    int x, y;

    inline Point(int _x = 0, int _y = 0) {
        x = _x, y = _y;
    }
    
    inline Point operator -(Point b) const {
        return Point(x - b.x, y - b.y);
    }

    inline ll operator *(Point b) const {
        return (ll)x * b.y - (ll)y * b.x;
    }
} cur;

int tp, m, mx, n, mxr;
bitset <maxn> done;
vector <Point> vc[maxn];

inline void Merge(int ls, int rs, int ff) {
    done[ff] = 1;
    int i, j, l1, l2, l3;
    vc[ff].clear(), l1 = vc[ls].size(), l2 = vc[rs].size();
    for (i = j = l3 = 0; i < l1 || j < l2; ) {
        if (j == l2 || (i < l1 && (vc[ls][i].x < vc[rs][j].x || (vc[ls][i].x == vc[rs][j].x && vc[ls][i].y < vc[rs][j].y)))) {
            while (l3 > 1 && (vc[ff][l3 - 1] - vc[ff][l3 - 2]) * (vc[ls][i] - vc[ff][l3 - 2]) >= 0) vc[ff].pop_back(), --l3;
            vc[ff].push_back(vc[ls][i]), ++i, ++l3;
        }
        else {
            while (l3 > 1 && (vc[ff][l3 - 1] - vc[ff][l3 - 2]) * (vc[rs][j] - vc[ff][l3 - 2]) >= 0) vc[ff].pop_back(), --l3;
            vc[ff].push_back(vc[rs][j]), ++j, ++l3;
        }
    }
}

inline ll Calc(int x) {
    if (!vc[x].size()) return -inf;
    int l, r, mid, ans;
    ans = vc[x].size() - 1, l = 0, r = vc[x].size() - 2;
    while (l <= r) {
        mid = (l + r) >> 1;
        if ((vc[x][mid + 1] - vc[x][mid]) * cur >= 0) ans = mid, r = mid - 1;
        else l = mid + 1;
    }
    return Point(cur.x, cur.y) * vc[x][ans];
}

void Insert(int x, int l, int r, int p) {
    int mid;
    if (l == r) {
        mxr = max(mxr, x);
        vc[x].push_back(cur), done[x] = 1;
        return;
    }
    mid = (l + r) >> 1;
    p <= mid ? Insert(x << 1, l, mid, p) : Insert(x << 1 | 1, mid + 1, r, p);
    if (x == (x & -x)) return;
    if (p == r && !done[x - 1]) Merge((x - 1) << 1, (x - 1) << 1 | 1, x - 1);
}

void Delete(int x, int l, int r, int p) {
    int mid;
    done[x] = 0;
    if (l == r) {
        mxr = max(mxr, x);
        vc[x].pop_back();
        return;
    }
    mid = (l + r) >> 1;
    p <= mid ? Delete(x << 1, l, mid, p) : Delete(x << 1 | 1, mid + 1, r, p);
}

ll Query(int x, int l, int r, int ql, int qr) {
    int mid;
    ll ret;
    if (ql <= l && qr >= r && done[x]) return Calc(x);
    if (l == r) return -inf;
    ret = -inf, mid = (l + r) >> 1;
    if (ql <= mid) ret = Query(x << 1, l, mid, ql, qr);
    if (qr > mid) ret = max(ret, Query(x << 1 | 1, mid + 1, r, ql, qr));
    return ret;
}

int main() {
    int i, op, x, y, l, r, ans;
    In(tp);
    while (In(m), m) {
        ans = n = 0, done.reset();
        for (i = 1; i <= mxr; ++i) vc[i].clear();
        for (mxr = 0, mx = 1; mx <= 300000; mx <<= 1);
        for (i = 1; i <= m; ++i) {
            In(op);
            if (op == 1) In(x), In(y), cur = Point(x, y), Insert(1, 1, mx, ++n);
            else if (op == 2) Delete(1, 1, mx, n), --n;
            else {
                In(l), In(r), In(x), In(y), cur = Point(x, y);
                ans ^= (Query(1, 1, mx, l, r) % mod + mod) % mod;
            }
        }
        printf("%d\n", ans);
    }
    return 0;
}
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