Submission #1157501

#	Time	Username	Problem	Language	Result	Execution time	Memory
1157501		DaciejMaciej	Valley (BOI19_valley)	C++20	23 / 100	157 ms	51892 KiB

valley

#include <bits/stdc++.h>
// #include <ext/pb_ds/assoc_container.hpp>
// #include <ext/pb_ds/tree_policy.hpp>
// #include <ext/rope>

using namespace std;
// using namespace __gnu_pbds;

typedef long long ll;
typedef unsigned long long ull;
typedef unsigned int uint;
typedef long double ld;

template <class T>

using VV = vector<vector<T>>;

using VI = vector<int>;
using VVI = vector<vector<int>>;

using VL = vector<long long>;
using VVL = vector<vector<long long>>;

using VC = vector<char>;
using VVC = vector<vector<char>>;

using VB = vector<bool>;
using VVB = vector<vector<bool>>;

using VD = vector<double>;
using VVD = vector<vector<double>>;

using PII = pair<int, int>;
using PLL = pair<long long, long long>;
using PIL = pair<int, long long>;
using PLI = pair<long long, int>;

using VPII = vector<pair<int, int>>;
using VPLL = vector<pair<long long, long long>>;

#define LINE '\n'
#define SPACE ' '
#define PB push_back
#define FOR(i, a, b) for (int i = (a); i < (int(b)); i++)
#define FORE(i, a, b) for (int i = (a); i <= (int)((b)); i++)
#define ALL(x) x.begin(), x.end()
#define RALL(x) x.rbegin(), x.rend()
#define sq(a) ((a) * (a))
#define sz(x) ((int)x.size())

#define fastio()                      \
    ios_base::sync_with_stdio(false); \
    cin.tie(nullptr);                 \
    cout.tie(nullptr)
#define debug(x) cerr << #x << " = " << x << endl;

const ll MOD = 1e9 + 7;

template <class T>
inline void maxi(T &a, T b)
{
    a = max(a, b);
}

template <class T>
inline void mini(T &a, T b)
{
    a = min(a, b);
}

template <class T>
inline void addi(T &a, T b)
{
    a = (a + b) % MOD;
}

template <class T>
inline void subi(T &a, T b)
{
    a = (a - b + MOD) % MOD;
}

template <class T>
inline T add(T a, T b)
{
    return (a + b) % MOD;
}

template <class T>
inline T sub(T a, T b)
{
    return (a - b + MOD) % MOD;
}

template <class T>
inline T mul(T a, T b)
{
    return ((a % MOD) * (b % MOD)) % MOD;
}

constexpr ll binpow(ll a, ll b, ll mod)
{
    ll res = 1;
    while (b > 0)
    {
        if (b & 1)
        {
            res = (res * a) % mod;
        }
        a = (a * a) % mod;
        b >>= 1;
    }

    return res;
}

const ll INF = 1e17;
const int MAX_N = 1e5 + 3;
const int d = 18;

vector<pair<int, ll>> g[MAX_N];
VB shop(MAX_N, false);

VI in(MAX_N, -1), out(MAX_N, -1);

VL sm(MAX_N, 0);
VL dpdown(MAX_N, INF);
VVL dp(MAX_N, VL(d + 1, INF));
VVL up(MAX_N, VL(d + 1, 0));

int t = 0;
void dfs(int c, int p)
{
    if (shop[c])
        dpdown[c] = 0;
    
    in[c] = ++t;
    for (auto [v, cost] : g[c])
    {
        if (v == p)
            continue;
        sm[v] = sm[c] + cost;
        dfs(v, c);
        mini(dpdown[c], dpdown[v] + cost);
    }
    out[c] = ++t;
}

bool isanc(int a, int b)
{
    return in[a] <= in[b] && out[a] >= out[b];
}

void dlift(int c, int p)
{

    dp[c][0] = min(dpdown[c], (sm[c] - sm[p]) + dpdown[p]); // edge c-p
    up[c][0] = p;
    FOR(i, 1, d + 1)
    {
        int u = up[c][i - 1];
        up[c][i] = up[u][i - 1];
        
        ll fr = dp[c][i - 1];
        ll cost = sm[c] - sm[u]; // koszt na c-up[c][i-1]
        ll sc = dp[u][i - 1] + cost;
        dp[c][i] = min(fr, sc);
    }

    for (auto [v, _] : g[c])
    {
        if (v == p)
            continue;
        dlift(v, c);
    }
}

void query(int road_bottom, int orig)
{
    int c = orig;
    if (!isanc(road_bottom, c))
    {
        cout << "escaped" << LINE;
        return;
    }

    if(c == road_bottom) {
        ll ans = dpdown[c];
        cout << (ans >= INF ? "oo" : to_string(ans)) << LINE;
        return;
    }

    ll ans = dpdown[c];
  
    
    for (int i = d; i >= 0; i--)
    {
        if (isanc(up[c][i], road_bottom))
            continue;
        
        ll nw = dp[c][i] + sm[orig] - sm[up[c][i]];
        mini(ans, nw);
       
        c = up[c][i];

    }

    mini(ans, (sm[orig] - sm[road_bottom]) + dpdown[road_bottom]); 

    if(ans >= INF) {
        cout << "oo" << LINE;
    }
    else {
        cout << ans << LINE;
    }
}

void solve()
{
    int n, s, q, e;
    cin >> n >> s >> q >> e;

    VPII edges(n - 1);
    FOR(i, 0, n - 1)
    {
        int a, b;
        ll w;
        cin >> a >> b >> w;
        g[a].PB({b, w});
        g[b].PB({a, w});
        edges[i] = {a, b};
    }

    in[0] = -1;
    out[0] = 1e8;

    FOR(i, 0, s)
    {
        int c;
        cin >> c;
        shop[c] = true;
    }

    dfs(e, e);
    dlift(e, e);
    for (auto &[a, b] : edges)
    {
        if (!isanc(a, b))
            swap(a, b); // a must be anc of b

    }
    
    while (q--)
    {
        int id, c;
        cin >> id >> c;

        query(edges[id-1].second, c);
    }
}

int main()
{
    fastio();

    int t = 1;
    // cin >> t;

    while (t--)
        solve();
}

• Subtask 1: 0 / 9
• Subtask 2: 0 / 27
• Subtask 3: 23 / 23
• Subtask 4: 0 / 41