Submission #335447

# Submission time Handle Problem Language Result Execution time Memory
335447 2020-12-12T16:34:48 Z 12tqian Valley (BOI19_valley) C++17
100 / 100
1629 ms 61280 KB
#pragma GCC optimize ("O3")
#pragma GCC target ("sse4")

#include <algorithm>
#include <array>
#include <bitset>
#include <cassert>
#include <chrono>
#include <cmath>
#include <complex>
#include <cstdio>
#include <cstdlib>
#include <cstring>
#include <ctime>
#include <deque>
#include <iostream>
#include <iomanip>
#include <map>
#include <numeric>
#include <queue>
#include <random>
#include <set>
#include <stack>
#include <string>
#include <unordered_map>
#include <vector>
#include <ext/pb_ds/tree_policy.hpp>
#include <ext/pb_ds/assoc_container.hpp>

using namespace std;
using namespace __gnu_pbds;
template <class T> using Tree = tree<T, null_type, less<T>, rb_tree_tag,tree_order_statistics_node_update>;

typedef long long ll;
typedef long double ld;
typedef double db;
typedef string str;

typedef pair<int, int> pi;
typedef pair<ll, ll> pl;
typedef pair<db, db> pd;

typedef vector<int> vi;
typedef vector<bool> vb;
typedef vector<ll> vl;
typedef vector<db> vd;
typedef vector<str> vs;
typedef vector<pi> vpi;
typedef vector<pl> vpl;
typedef vector<pd> vpd;

#define mp make_pair
#define f first
#define s second
#define sz(x) (int) (x).size()
#define all(x) begin(x), end(x)
#define rall(x) (x).rbegin(), (x).rend()
#define sor(x) sort(all(x))
#define rsz resize
#define resz resize
#define ins insert
#define ft front()
#define bk back()
#define pf push_front
#define pb push_back
#define eb emplace_back
#define lb lower_bound
#define ub upper_bound

#define f1r(i, a, b) for(int i = (a); i < (b); ++i)
#define f0r(i, a) f1r(i, 0, a)
#define FOR(i, a, b) for (int i = (a); i < (b); ++i)
#define F0R(i, a) FOR(i,0,a)
#define ROF(i, a, b) for (int i = (b) - 1; i >= (a); --i)
#define R0F(i, a) ROF(i, 0, a)
#define trav(a, x) for (auto& a : x)

mt19937 rng((uint32_t) chrono::steady_clock::now().time_since_epoch().count());

template<class T> bool ckmin(T& a, const T& b) { return b < a ? a = b, 1 : 0; }
template<class T> bool ckmax(T& a, const T& b) { return a < b ? a = b, 1 : 0; }
template<class T> using V = vector<T>;

#ifdef LOCAL
#define dbg(...) debug(#__VA_ARGS__, __VA_ARGS__);
#else
#define dbg(...) 17;
#endif

template<typename T, typename S> ostream& operator << (ostream &os, const pair<T, S> &p) { return os << "(" << p.first << ", " << p.second << ")"; }
template<typename C, typename T = decay<decltype(*begin(declval<C>()))>, typename enable_if<!is_same<C, string>::value>::type* = nullptr>
ostream& operator << (ostream &os, const C &c) { bool f = true; os << "{"; for (const auto &x : c) { if (!f) os << ", "; f = false; os << x; } return os << "}"; }
template<typename T> void debug(string s, T x) { cerr << s << " = " << x << "\n"; }
template<typename T, typename... Args> void debug(string s, T x, Args... args) { cerr << s.substr(0, s.find(',')) << " = " << x << " | "; debug(s.substr(s.find(',') + 2), args...); }

constexpr int pct(int x) { return __builtin_popcount(x); }
constexpr int bits(int x) { return 31 - __builtin_clz(x); } // floor(log2(x))

namespace input {
    template<class T> void re(complex<T>& x);
    template<class T1, class T2> void re(pair<T1, T2>& p);
    template<class T> void re(vector<T>& a);
    template<class T, int SZ> void re(array<T, SZ>& a);
    template<class T> void re(T& x) { cin >> x; }
    void re(double& x) { string t; re(t); x = stod(t); }
    void re(ld& x) { string t; re(t); x = stold(t); }
    template<class T, class... Ts> void re(T& t, Ts&... ts) {
        re(t); re(ts...); }
    template<class T> void re(complex<T>& x) { T a, b; re(a, b); x = cd(a, b); }
    template<class T1, class T2> void re(pair<T1, T2>& p) { re(p.f, p.s); }
    template<class T> void re(vector<T>& a) { F0R(i, sz(a)) re(a[i]); }
    template<class T, int SZ> void re(array<T, SZ>& a) { F0R(i, SZ) re(a[i]); }
}

using namespace input;

namespace output {
    void pr(int x) { cout << x; }
    void pr(long x) { cout << x; }
    void pr(ll x) { cout << x; }
    void pr(unsigned x) { cout << x; }
    void pr(unsigned long x) { cout << x; }
    void pr(unsigned long long x) { cout << x; }
    void pr(float x) { cout << x; }
    void pr(double x) { cout << x; }
    void pr(ld x) { cout << x; }
    void pr(char x) { cout << x; }
    void pr(const char* x) { cout << x; }
    void pr(const string& x) { cout << x; }
    void pr(bool x) { pr(x ? "true" : "false"); }
    template<class T> void pr(const complex<T>& x) { cout << x; }
    template<class T1, class T2> void pr(const pair<T1, T2>& x);
    template<class T> void pr(const T& x);
    template<class T, class... Ts> void pr(const T& t, const Ts&... ts) {
        pr(t); pr(ts...); }
    template<class T1, class T2> void pr(const pair<T1,T2>& x) {
        pr("{", x.f, ", ", x.s, "}"); }
    template<class T> void pr(const T& x) {
        pr("{"); // const iterator needed for vector<bool>
        bool fst = 1; for (const auto& a: x) pr(!fst ? ", " : "", a), fst = 0;
        pr("}"); }
    void ps() { pr("\n"); } // print w/ spaces
    template<class T, class... Ts> void ps(const T& t, const Ts&... ts) {
        pr(t); if (sizeof...(ts)) pr(" "); ps(ts...); }
    void pc() { pr("]\n"); } // debug w/ commas
    template<class T, class... Ts> void pc(const T& t, const Ts&... ts) {
        pr(t); if (sizeof...(ts)) pr(", "); pc(ts...); }
}

using namespace output;

namespace io {
    void setIn(string s) { freopen(s.c_str(), "r", stdin); }
    void setOut(string s) { freopen(s.c_str(), "w", stdout); }
    void setIO(string s = "") {
        cin.sync_with_stdio(0); cin.tie(0);
        if (sz(s)) { setIn(s + ".in"), setOut(s + ".out"); }
    }
}

using namespace io;

const int MOD = 1e9 + 7; // 998244353;
const ld PI = acos((ld) -1);

typedef std::decay <decltype(MOD)>::type mod_t;
struct mi {
    mod_t val;
    explicit operator mod_t() const { return val; }
    mi() { val = 0; }
    mi(const long long& v) {
        val = (-MOD <= v && v <= MOD) ? v : v % MOD;
        if (val < 0) val += MOD; }
    friend std::istream& operator >> (std::istream& in, mi& a) {
        long long x; std::cin >> x; a = mi(x); return in; }
    friend std::ostream& operator << (std::ostream& os, const mi& a) { return os << a.val; }
    friend bool operator == (const mi& a, const mi& b) { return a.val == b.val; }
    friend bool operator != (const mi& a, const mi& b) { return !(a == b); }
    friend bool operator < (const mi& a, const mi& b) { return a.val < b.val; }
    friend bool operator > (const mi& a, const mi& b) { return a.val > b.val; }
    friend bool operator <= (const mi& a, const mi& b) { return a.val <= b.val; }
    friend bool operator >= (const mi& a, const mi& b) { return a.val >= b.val; }
    mi operator - () const { return mi(-val); }
    mi& operator += (const mi& m) {
        if ((val += m.val) >= MOD) val -= MOD;
        return *this; }
    mi& operator -= (const mi& m) {
        if ((val -= m.val) < 0) val += MOD;
        return *this; }
    mi& operator *= (const mi& m) { val = (long long) val * m.val % MOD;
        return *this; }
    friend mi pow(mi a, long long p) {
        mi ans = 1; assert(p >= 0);
        for (; p; p /= 2, a *= a) if (p & 1) ans *= a;
        return ans; }
    friend mi inv(const mi& a) { assert(a != 0); return pow(a, MOD - 2); }
    mi& operator /= (const mi& m) { return (*this) *= inv(m); }
    friend mi operator + (mi a, const mi& b) { return a += b; }
    friend mi operator - (mi a, const mi& b) { return a -= b; }
    friend mi operator * (mi a, const mi& b) { return a *= b; }
    friend mi operator / (mi a, const mi& b) { return a /= b; }
};
typedef pair<mi, mi> pmi;
typedef vector<mi> vmi;
typedef vector<pmi> vpmi;

const ll INF = 1e16;
const ll CUT = 1e14 + 1;

template <class T> struct LazySeg {
    std::vector<T> mn, lazy;
    int sz;
    void init(int sz_) {
        sz = 1;
        while (sz < sz_) sz *= 2;
        mn.assign(2 * sz, 0);
        lazy.assign(2 * sz, 0);
    }
    void push(int ind, int L, int R) {
        mn[ind] += lazy[ind];
        if (L != R) {
            lazy[2 * ind] += lazy[ind];
            lazy[2 * ind + 1] += lazy[ind];
        }
        lazy[ind] = 0;
    }
    void pull(int ind) {
        mn[ind] = min(mn[2 * ind], mn[2 * ind + 1]);
    }
    void build() {
        for (int i = sz - 1; i >= 1; i--) {
            pull(i);
        }
    }
    void upd(int lo, int hi, T inc, int ind = 1, int L = 0, int R = -1) {
        if (R == -1) R += sz;
        push(ind, L, R);
        if (hi < L || R < lo) return ;
        if (lo <= L && R <= hi) {
            lazy[ind] = inc;
            push(ind, L, R);
            return;
        }
        int M = (L + R) / 2;
        upd(lo, hi, inc, 2 * ind, L, M);
        upd(lo, hi, inc, 2 * ind + 1, M + 1, R);
        pull(ind);
    }
    T qmin(int lo, int hi, int ind = 1, int L = 0, int R = -1) {
        if (R == -1) R += sz;
        push(ind, L, R);
        if (lo > R || L > hi) return INF;
        if (lo <= L && R <= hi) return mn[ind];
        int M = (L + R) / 2;
        return min(qmin(lo, hi, 2 * ind, L, M), qmin(lo, hi, 2 * ind + 1, M + 1, R));
    }
};
struct LCAJump {
    int n;
    std::vector<std::vector<int>> par;
    std::vector<std::vector<int>> adj;
    std::vector<int> depth;
    void init(int _n) {
        n = _n;
        int d = 1;
        while ((1 << d) < n) d++;
        par.assign(d, std::vector<int>(n));
        adj.resize(n);
        depth.resize(n);
    }
    void ae(int x, int y) {
        adj[x].push_back(y);
        adj[y].push_back(x);
    }
    void gen(int root = 0) {
        par[0][root] = root;
        dfs(root);
    }
    void dfs(int src = 0) {
        for (int i = 1; i < (int) par.size(); i++) {
            par[i][src] = par[i - 1][par[i - 1][src]];
        }
        for (int nxt: adj[src]) {
            if (nxt == par[0][src]) continue;
            depth[nxt] = depth[par[0][nxt] = src] + 1;
            dfs(nxt);
        }
    }
    int jump(int x, int d) {
        for (int i = 0; i < (int) par.size(); i++) {
            if ((d >> i) & 1) {
                x = par[i][x];
            }
        }
        return x;
    }
    int lca(int x, int y) {
        if (depth[x] < depth[y]) std::swap(x, y);
        x = jump(x, depth[x] - depth[y]);
        if (x == y) return x;
        for (int i = (int) par.size() - 1; i >= 0; i--) {
            int nx = par[i][x];
            int ny = par[i][y];
            if (nx != ny) x = nx, y = ny;
        }
        return par[0][x];
    }
    bool in_subtree(int u, int v) {
        // is v in the subtree of u
        if (depth[u] > depth[v]) return false;
        int need = depth[v] - depth[u];
        int x = jump(v, need);
        if (x == u) return true;
        return false;
    }
};
int main() {
    int n, s, e, q; cin >> n >> s >> q >> e;
    e--;

    LCAJump L;
    L.init(n);

    vector<vpl> adj(n);
    vpi roads;
    vi shop(n);

    f0r(i, n - 1) {
        int u, v, w; cin >> u >> v >> w;
        u--, v--;
        adj[u].eb(v, w);
        adj[v].eb(u, w);
        L.ae(u, v);
        roads.eb(u, v);
    }

    f0r(i, s) {
        int x; re(x); x--;
        shop[x] = 1;
    }

    int ti = 0;
    vector<array<int, 2>> range(n);
    vl dep(n);

    function<void(int, int)> euler_tour = [&](int src, int par) {
        range[src][0] = ti++;
        for (auto nxt : adj[src]) {
            if (nxt.f == par) continue;
            dep[nxt.f] = dep[src] + nxt.s;
            euler_tour(nxt.f, src);
        }
        range[src][1] = ti-1;
    };
    
    L.gen(0);
    euler_tour(0, -1);
    LazySeg<ll> seg;
    seg.init(n);
    LazySeg<ll> seg2;
    seg2.init(n);

    f0r(i, n) {
        if (shop[i]) 
            seg.upd(range[i][0], range[i][0], dep[i]);
        else
            seg.upd(range[i][0], range[i][0], INF);
        seg2.upd(range[i][0], range[i][0], dep[i]);
    }


    vl ans(q);
    vl close(q);
    vl escape(q);
    vector<vpi> queries(n);
    vector<array<int, 3>> queries2;

    f0r(i, q) {
        int road, village;
        re(road, village);
        road--, village--;
        queries[village].eb(road, i);
        queries2.pb({road, village, i});
    }
    
    auto sub_update = [&](int src, ll val) {
        seg.upd(range[src][0], range[src][1], val);
    };
    auto sub_update2 = [&](int src, ll val) {
        seg2.upd(range[src][0], range[src][1], val);
    };
    auto ask = [&](int src) -> ll {
        return seg.qmin(range[src][0], range[src][1]);
    };
    auto print = [&]() {
        pr("SEG: ");
        f0r(i, n) pr(seg.qmin(range[i][0], range[i][0]),  " ");
        ps();
    };
    function<void(int, int)> reroot = [&](int src, int par) {
        // answer close queries here
        for (auto& qq : queries[src]) {
            int qid = qq.s;
            int rid = qq.f;
            int u = roads[rid].f;
            int v = roads[rid].s;
            if (dep[u] > dep[v]) swap(u, v);
            // u is parent of v
            // want to see closest of shops to src
            // case one, shop is below
            if (L.in_subtree(v, src)) {
                // everything else above is blocked
                sub_update(0, INF);
                sub_update(v, -INF);
                close[qid] = ask(v);
                
                sub_update(0, -INF);
                sub_update(v, INF);
            } else {
                // everthing in v is blocked
                sub_update(v, INF);
                close[qid] = ask(0);
                sub_update(v, -INF);
            }
        }
        // answer can escape queries
        if (src == e) {
            // you are at the escape point
            for (auto& qq : queries2) {
                int qid = qq[2];
                int rid = qq[0];
                int vid = qq[1];
                int u = roads[rid].f;
                int v = roads[rid].s;

                if (dep[u] > dep[v]) swap(u, v);
               
                if (L.in_subtree(v, src)) {
                    // everything else above is blocked
                    sub_update2(0, INF);
                    sub_update2(v, -INF);
                    escape[qid] = seg2.qmin(range[vid][0], range[vid][0]);
                    sub_update2(0, -INF);
                    sub_update2(v, INF);
                } else {
                    // everthing in v is blocked
                    sub_update2(v, INF);
                    escape[qid] = seg2.qmin(range[vid][0], range[vid][0]);
                    sub_update2(v, -INF);
                }
            }
        }
        for (auto go : adj[src]) { 
            int nxt = go.f;
            if (nxt == par) continue;
            int w = go.s;
            sub_update(0, w);
            sub_update(nxt, -2*w);

            sub_update2(0, w);
            sub_update2(nxt, -2*w);

            reroot(nxt, src);

            sub_update(0, -w);
            sub_update(nxt, 2*w);

            sub_update2(0, -w);
            sub_update2(nxt, 2*w);
        }
    };
    reroot(0, -1);
    f0r(i, q) {
        if (escape[i] < CUT) {
            ps("escaped");
        } else {
            if (close[i] < CUT) {
                ps(close[i]);
            } else {
                ps("oo");
            }
        }
    }
}

Compilation message

valley.cpp: In function 'int main()':
valley.cpp:395:10: warning: variable 'print' set but not used [-Wunused-but-set-variable]
  395 |     auto print = [&]() {
      |          ^~~~~
valley.cpp: In function 'void io::setIn(std::string)':
valley.cpp:153:35: warning: ignoring return value of 'FILE* freopen(const char*, const char*, FILE*)', declared with attribute warn_unused_result [-Wunused-result]
  153 |     void setIn(string s) { freopen(s.c_str(), "r", stdin); }
      |                            ~~~~~~~^~~~~~~~~~~~~~~~~~~~~~~
valley.cpp: In function 'void io::setOut(std::string)':
valley.cpp:154:36: warning: ignoring return value of 'FILE* freopen(const char*, const char*, FILE*)', declared with attribute warn_unused_result [-Wunused-result]
  154 |     void setOut(string s) { freopen(s.c_str(), "w", stdout); }
      |                             ~~~~~~~^~~~~~~~~~~~~~~~~~~~~~~~
# Verdict Execution time Memory Grader output
1 Correct 16 ms 1004 KB Output is correct
2 Correct 17 ms 1132 KB Output is correct
3 Correct 17 ms 1132 KB Output is correct
4 Correct 17 ms 1132 KB Output is correct
# Verdict Execution time Memory Grader output
1 Correct 16 ms 1004 KB Output is correct
2 Correct 17 ms 1132 KB Output is correct
3 Correct 17 ms 1132 KB Output is correct
4 Correct 17 ms 1132 KB Output is correct
5 Correct 6 ms 748 KB Output is correct
6 Correct 8 ms 748 KB Output is correct
7 Correct 6 ms 748 KB Output is correct
8 Correct 6 ms 748 KB Output is correct
9 Correct 6 ms 748 KB Output is correct
10 Correct 7 ms 748 KB Output is correct
11 Correct 6 ms 748 KB Output is correct
12 Correct 6 ms 896 KB Output is correct
13 Correct 6 ms 748 KB Output is correct
14 Correct 6 ms 748 KB Output is correct
# Verdict Execution time Memory Grader output
1 Correct 1249 ms 40572 KB Output is correct
2 Correct 1305 ms 43800 KB Output is correct
3 Correct 1284 ms 43868 KB Output is correct
4 Correct 1439 ms 49612 KB Output is correct
5 Correct 1341 ms 47848 KB Output is correct
6 Correct 1629 ms 61280 KB Output is correct
# Verdict Execution time Memory Grader output
1 Correct 16 ms 1004 KB Output is correct
2 Correct 17 ms 1132 KB Output is correct
3 Correct 17 ms 1132 KB Output is correct
4 Correct 17 ms 1132 KB Output is correct
5 Correct 6 ms 748 KB Output is correct
6 Correct 8 ms 748 KB Output is correct
7 Correct 6 ms 748 KB Output is correct
8 Correct 6 ms 748 KB Output is correct
9 Correct 6 ms 748 KB Output is correct
10 Correct 7 ms 748 KB Output is correct
11 Correct 6 ms 748 KB Output is correct
12 Correct 6 ms 896 KB Output is correct
13 Correct 6 ms 748 KB Output is correct
14 Correct 6 ms 748 KB Output is correct
15 Correct 1249 ms 40572 KB Output is correct
16 Correct 1305 ms 43800 KB Output is correct
17 Correct 1284 ms 43868 KB Output is correct
18 Correct 1439 ms 49612 KB Output is correct
19 Correct 1341 ms 47848 KB Output is correct
20 Correct 1629 ms 61280 KB Output is correct
21 Correct 1183 ms 43756 KB Output is correct
22 Correct 1246 ms 43232 KB Output is correct
23 Correct 1251 ms 43344 KB Output is correct
24 Correct 1415 ms 47344 KB Output is correct
25 Correct 1389 ms 56844 KB Output is correct
26 Correct 1195 ms 43656 KB Output is correct
27 Correct 1222 ms 43356 KB Output is correct
28 Correct 1262 ms 43364 KB Output is correct
29 Correct 1374 ms 48624 KB Output is correct
30 Correct 1436 ms 53340 KB Output is correct
31 Correct 1167 ms 43880 KB Output is correct
32 Correct 1200 ms 43356 KB Output is correct
33 Correct 1247 ms 43428 KB Output is correct
34 Correct 1366 ms 47640 KB Output is correct
35 Correct 1350 ms 55004 KB Output is correct
36 Correct 1309 ms 48988 KB Output is correct