UOJ#191. 【集训队互测2016】Unknown

传送门
这个题目实际上可以建立出树,然后重链剖分维护一条链的凸包
然后离线询问排序斜率做到 \(nlog^2n\),或者点分治+平衡树也行
但是这个题目卡空间,数组一不小心就爆了卡一卡也能过
考虑其它空间常数小并且又好写的做法
根据一般的二进制分组的方法,每次这个块满了就合并儿子的凸包
这样显然不对,只要又删又加就假了
我们换一种方法,每次这个块满了就合并线段树同一层前一个节点的儿子的凸包
这样每次都要花费 \(len\) 次添加操作才能换来一次 \(2len\) 的合并
此时的没有合并节点顶多 \(2log\)
查询就定位每个节点,在凸包上二分即可
时间 \(nlog^2n\) 空间 \(nlogn\)

# include 
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  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  done;
vector  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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