Codeforces 173E Camping Groups 线段树

Camping Groups

我们先计算出， 每个点当leader所能掌控的最多人数。 然后我们把询问离线， 丢到responsibility最大的那个地方去。

然后从大到小往线段树里加人， 加入完之后处理掉当前的询问。

 

如果强制在线的话就只能树套树啦。

#include<bits/stdc++.h>
#define LL long long
#define LD long double
#define ull unsigned long long
#define fi first
#define se second
#define mk make_pair
#define PLL pair<LL, LL>
#define PLI pair<LL, int>
#define PII pair<int, int>
#define SZ(x) ((int)x.size())
#define ALL(x) (x).begin(), (x).end()
#define fio ios::sync_with_stdio(false); cin.tie(0);

using namespace std;

const int N = 1e5 + 7;
const int inf = 0x3f3f3f3f;
const LL INF = 0x3f3f3f3f3f3f3f3f;
const int mod = 1e9 + 7;
const double eps = 1e-8;
const double PI = acos(-1);

template<class T, class S> inline void add(T& a, S b) {a += b; if(a >= mod) a -= mod;}
template<class T, class S> inline void sub(T& a, S b) {a -= b; if(a < 0) a += mod;}
template<class T, class S> inline bool chkmax(T& a, S b) {return a < b ? a = b, true : false;}
template<class T, class S> inline bool chkmin(T& a, S b) {return a > b ? a = b, true : false;}

int n, k, q;
int a[N], r[N];
int c[N];

int hsa[N], tota;
int hsr[N], totr;

int ans[N];

vector<PII> vc[N];
vector<pair<PII, int>> qus[N];

struct Bit {
    int a[N];
    void modify(int x, int v) {
        for(int i = x; i < N; i += i & -i) a[i] += v;
    }
    int sum(int x) {
        int ans = 0;
        for(int i = x; i; i -= i & -i) ans += a[i];
        return ans;
    }
    int query(int L, int R) {
        if(L > R) return 0;
        return sum(R) - sum(L - 1);
    }
} bit;

struct SegmentTree {
#define lson l, mid, rt << 1
#define rson mid + 1, r, rt << 1 | 1
    int mx[N << 2];
    inline void pull(int rt) {
        mx[rt] = max(mx[rt << 1], mx[rt << 1 | 1]);
    }
    void update(int L, int R, int val, int l, int r, int rt) {
        if(R < l || r < L || R < L) return;
        if(L <= l && r <= R) {
            chkmax(mx[rt], val);
            return;
        }
        int mid = l + r >> 1;
        update(L, R, val, lson);
        update(L, R, val, rson);
        pull(rt);
    }
    int query(int L, int R, int l, int r, int rt) {
        if(R < l || r < L || R < L) return 0;
        if(L <= l && r <= R) return mx[rt];
        int mid = l + r >> 1;
        return max(query(L, R, lson), query(L, R, rson));
    }
} Tree;

int getPosa(int x) {
    return lower_bound(hsa + 1, hsa + 1 + tota, x) - hsa;
}
int getPosr(int x) {
    return lower_bound(hsr + 1, hsr + 1 + totr, x) - hsr;
}

int main() {
    memset(ans, -1, sizeof(ans));
    scanf("%d%d", &n, &k);
    for(int i = 1; i <= n; i++) scanf("%d", &a[i]), hsa[++tota] = a[i];
    for(int i = 1; i <= n; i++) scanf("%d", &r[i]), hsr[++totr] = r[i];
    sort(hsa + 1, hsa + 1 + tota); tota = unique(hsa + 1, hsa + 1 + tota) - hsa - 1;
    sort(hsr + 1, hsr + 1 + totr); totr = unique(hsr + 1, hsr + 1 + totr) - hsr - 1;

    for(int i = 1; i <= n; i++) {
        vc[lower_bound(hsa + 1, hsa + 1 + tota, a[i]) - hsa].push_back(mk(r[i], 0));
    }

    for(int i = 1; i <= tota; i++) {
        for(auto& t : vc[i]) bit.modify(getPosr(t.fi), 1);
        for(auto& t : vc[i]) {
            t.se = bit.query(getPosr(t.fi - k), getPosr(t.fi + k + 1) - 1);
        }
    }
    scanf("%d", &q);
    for(int i = 1; i <= q; i++) {
        int x, y; scanf("%d%d", &x, &y);
        int maxa = max(a[x], a[y]);
        if(r[x] > r[y]) swap(x, y);
        qus[lower_bound(hsa + 1, hsa + 1 + tota, maxa) - hsa].push_back(mk(mk(r[y] - k, r[x] + k), i));
    }
    for(int i = tota; i >= 1; i--) {
        for(auto& t : vc[i]) Tree.update(getPosr(t.fi), getPosr(t.fi), t.se, 1, totr, 1);
        for(auto& q : qus[i]) ans[q.se] = Tree.query(getPosr(q.fi.fi), getPosr(q.fi.se + 1) - 1, 1, totr, 1);
    }
    for(int i = 1; i <= q; i++) printf("%d\n", ans[i] == 0 ? -1 : ans[i]);
    return 0;
}

/*
*/