Submission #974477

#	Time	Username	Problem	Language	Result	Execution time	Memory
974477		Mher777	Valley (BOI19_valley)	C++17	100 / 100	254 ms	35328 KiB

valley

#define _CRT_SECURE_NO_WARNINGS
#include <iostream>
#include <iomanip>
#include <array>
#include <string>
#include <algorithm>
#include <cmath>
#include <set>
#include <map>
#include <unordered_set>
#include <unordered_map>
#include <vector>
#include <stack>
#include <queue>
#include <deque>
#include <bitset>
#include <list>
#include <iterator>
#include <numeric>
#include <complex>
#include <utility>
#include <random>
#include <cassert>
#include <fstream>
using namespace std;
mt19937 rnd(7069);

/* -------------------- Typedefs -------------------- */

typedef int itn;
typedef long long ll;
typedef unsigned long long ull;
typedef double db;
typedef float fl;
typedef long double ld;

/* -------------------- Usings -------------------- */

using vi = vector<int>;
using vll = vector<ll>;
using mii = map<int, int>;
using mll = map<ll, ll>;
using pii = pair<int, int>;
using pll = pair<ll, ll>;

/* -------------------- Defines -------------------- */

#define ff first
#define ss second
#define pub push_back
#define pob pop_back
#define puf push_front
#define pof pop_front
#define mpr make_pair
#define yes cout<<"Yes\n"
#define no cout<<"No\n"
#define all(x) (x).begin(), (x).end()
#define USACO freopen("feast.in", "r", stdin); freopen("feast.out", "w", stdout);

/* -------------------- Constants -------------------- */

const int dx[8] = { -1, 0, 1, 0, -1, -1, 1, 1 };
const int dy[8] = { 0, -1, 0, 1, -1, 1, -1, 1 };
const int MAX = int(2e9 + 5);
const ll MAXL = ll(1e18) + 5ll;
const ll MOD = ll(1000000007);
const ll MOD2 = ll(998244353);

/* -------------------- Functions -------------------- */

void fastio() {
    ios_base::sync_with_stdio(false);
    cin.tie(0);
    cout.tie(0);
}

void precision(int x) {
    cout.setf(ios::fixed | ios::showpoint);
    cout.precision(x);
}

ll gcd(ll a, ll b) {
    if (a == 0 || b == 0) return(max(a, b));
    while (b) {
        a %= b;
        swap(a, b);
    }
    return a;
}

ll lcm(ll a, ll b) {
    return a / gcd(a, b) * b;
}

ll range_sum(ll a, ll b) {
    if (a > b) return 0ll;
    ll dif = a - 1, cnt = b - a + 1;
    ll ans = ((b - a + 1) * (b - a + 2)) / 2;
    ans += ((b - a + 1) * dif);
    return ans;
}

string dec_to_bin(ll a) {
    string s = "";
    for (ll i = a; i > 0; ) {
        ll k = i % 2;
        i /= 2;
        char c = k + 48;
        s += c;
    }
    if (a == 0) {
        s = "0";
    }
    reverse(all(s));
    return s;
}

ll bin_to_dec(string s) {
    ll num = 0;
    for (int i = 0; i < s.size(); i++) {
        num *= 2ll;
        num += (s[i] - '0');
    }
    return num;
}

ll factorial_by_mod(ll n, ll mod) {
    ll ans = 1;
    ll num;
    for (ll i = 1; i <= n; ++i) {
        num = i % mod;
        ans *= num;
        ans %= mod;
    }
    return ans;
}

int isPrime(ll a) {
    if (a == 1) return 0;
    for (ll i = 2; i * i <= a; i++) {
        if (a % i == 0) return 0;
    }
    return 1;
}

ll binpow(ll a, ll b) {
    if (!a) return 0;
    ll ans = 1;
    while (b) {
        if (b & 1) {
            ans *= a;
        }
        b >>= 1;
        a *= a;
    }
    return ans;
}

ll binpow_by_mod(ll a, ll b, ll mod) {
    if (!a) return 0;
    ll ans = 1;
    while (b) {
        if (b & 1) {
            ans *= a;
            ans %= mod;
        }
        b >>= 1;
        a *= a;
        a %= mod;
    }
    return ans;
}

/* -------------------- Solution -------------------- */

const int N = 100005;
int id[N], tin[N], tout[N], till[N], shop[N];
ll t[N * 4], lazy[N * 4], ran[N * 4], dist[N], ans[N];
vi nodes;
vector<pii> edge;
vector<pii> har[N];
vector<pair<int, ll>> g[N];
int n, sz, s, q, e, timer;

void prop(int pos) {
    if (!lazy[pos]) return;
    t[2 * pos] += lazy[pos];
    t[2 * pos + 1] += lazy[pos];
    lazy[2 * pos] += lazy[pos];
    lazy[2 * pos + 1] += lazy[pos];
    lazy[pos] = 0;
}

void bld(int l = 1, int r = n, int pos = 1) {
    if (l == r) {
        t[pos] = dist[l];
        return;
    }
    int mid = (l + r) / 2;
    bld(l, mid, 2 * pos);
    bld(mid + 1, r, 2 * pos + 1);
    t[pos] = min(t[2 * pos], t[2 * pos + 1]);
}

ll qry(int l, int r, int tl = 1, int tr = n, int pos = 1) {
    if (l == tl && r == tr) {
        return t[pos];
    }
    prop(pos);
    int mid = (tl + tr) / 2;
    if (mid >= r) {
        return qry(l, r, tl, mid, 2 * pos);
    }
    if (mid < l) {
        return qry(l, r, mid + 1, tr, 2 * pos + 1);
    }
    return min(qry(l, mid, tl, mid, 2 * pos), qry(mid + 1, r, mid + 1, tr, 2 * pos + 1));
}

void upd(int l, int r, ll val, int tl = 1, int tr = n, int pos = 1) {
    if (r < l) return;
    if (l == tl && r == tr) {
        t[pos] += val;
        lazy[pos] += val;
        return;
    }
    prop(pos);
    int mid = (tl + tr) / 2;
    if (mid >= r) {
        upd(l, r, val, tl, mid, 2 * pos);
    }
    else if (mid < l) {
        upd(l, r, val, mid + 1, tr, 2 * pos + 1);
    }
    else {
        upd(l, mid, val, tl, mid, 2 * pos);
        upd(mid + 1, r, val, mid + 1, tr, 2 * pos + 1);
    }
    t[pos] = min(t[2 * pos], t[2 * pos + 1]);
}

void dfs(int u = e, int p = e, ll w = 0) {
    id[u] = ++sz;
    tin[u] = ++timer;
    dist[id[u]] = MAXL;
    if (shop[u]) {
        dist[id[u]] = w;
        nodes.pub(id[u]);
    }
    for (auto to : g[u]) {
        if (to.ff == p) continue;
        dfs(to.ff, u, w + to.ss);
    }
    tout[u] = ++timer;
    till[u] = sz;
}

bool upper(int x, int y) {
    return tin[x] <= tin[y] && tout[x] >= tout[y];
}

void dfs1(int u = e, int p = e, ll w = 0) {
    int l = id[u], r = till[u];
    upd(l, r, -w);
    upd(1, l - 1, w);
    upd(r + 1, n, w);
    for (auto elem : har[u]) {
        int edge_ind = elem.ff, ind = elem.ss;
        int u1 = edge[edge_ind].ff, u2 = edge[edge_ind].ss;
        if (!upper(u2, u)) {
            ans[ind] = -1;
            continue;
        }
        if (upper(u2, u)) u1 = u2;
        int lx = id[u1], rx = till[u1];
        int index1 = lower_bound(all(nodes), lx) - nodes.begin();
        int index2 = upper_bound(all(nodes), rx) - nodes.begin() - 1;
        if (index1 > index2) {
            ans[ind] = MAXL;
            continue;
        }
        ans[ind] = qry(lx, rx);
    }
    for (auto to : g[u]) {
        if (to.ff == p) continue;
        dfs1(to.ff, u, to.ss);
    }
    upd(l, r, w);
    upd(1, l - 1, -w);
    upd(r + 1, n, -w);
}

void slv() {
    cin >> n >> s >> q >> e;
    vi vec(s);
    for (int i = 0; i < n - 1; ++i) {
        int x, y;
        ll w;
        cin >> x >> y >> w;
        edge.pub({ x,y });
        g[x].pub({ y,w });
        g[y].pub({ x,w });
    }
    for (int i = 0; i < s; ++i) {
        cin >> vec[i];
        shop[vec[i]] = 1;
    }
    dfs();
    for (auto& elem : edge) {
        if (!upper(elem.ff, elem.ss)) swap(elem.ff, elem.ss);
    }
    for (int i = 0; i < q; ++i) {
        int x, y;
        cin >> x >> y;
        har[y].pub({ x - 1,i });
    }
    bld();
    dfs1();
    for (int i = 0; i < q; ++i) {
        if (ans[i] == -1) cout << "escaped";
        else if (ans[i] == MAXL) cout << "oo";
        else cout << ans[i];
        cout << '\n';
    }
}

void cs() {
    int tstc = 1;
    //cin >> tstc;
    while (tstc--) {
        slv();
    }
}

void precalc() {
    return;
}

int main() {
    fastio();
    precalc();
    //precision(0);
    cs();
    return 0;
}

Compilation message (stderr)

valley.cpp: In function 'll range_sum(ll, ll)':
valley.cpp:97:21: warning: unused variable 'cnt' [-Wunused-variable]
   97 |     ll dif = a - 1, cnt = b - a + 1;
      |                     ^~~
valley.cpp: In function 'll bin_to_dec(std::string)':
valley.cpp:120:23: warning: comparison of integer expressions of different signedness: 'int' and 'std::__cxx11::basic_string<char>::size_type' {aka 'long unsigned int'} [-Wsign-compare]
  120 |     for (int i = 0; i < s.size(); i++) {
      |                     ~~^~~~~~~~~~

• Subtask 1: 9 / 9
• Subtask 2: 27 / 27
• Subtask 3: 23 / 23
• Subtask 4: 41 / 41