oj.uz

답안 #366868

# 제출 시각 아이디 문제 언어 결과 실행 시간 메모리
366868 2021-02-15T14:07:33 Z ACmachine Valley (BOI19_valley) C++17
100 / 100
 472 ms 50028 KB 
#include <bits/stdc++.h>
using namespace std;

#include <ext/pb_ds/assoc_container.hpp>
#include <ext/pb_ds/tree_policy.hpp>
using namespace __gnu_pbds;

template<typename T> using ordered_set = tree<T, null_type, less<T>, rb_tree_tag, tree_order_statistics_node_update>;
template<typename T, typename U> using ordered_map = tree<T, U, 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> pii;
typedef pair<ll,ll> pll;

typedef vector<int> vi;
typedef vector<ll> vll;
typedef vector<pii> vpii;
typedef vector<pll> vpll;
typedef vector<str> vstr;

#define FOR(i,j,k,in) for(int i=(j); i < (k);i+=in)
#define FORD(i,j,k,in) for(int i=(j); i >=(k);i-=in)
#define REP(i,b) FOR(i,0,b,1)
#define REPD(i,b) FORD(i,b,0,1)
#define pb push_back 
#define mp make_pair
#define ff first
#define ss second
#define all(x) begin(x), end(x)
#define rsz resize 
#define MANY_TESTS int tcase; cin >> tcase; while(tcase--)
	
const double EPS = 1e-9;
const int MOD = 1e9+7; // 998244353;
const ll INFF = 1e18;
const int INF = 1e9;
const ld PI = acos((ld)-1);
const vi dy = {1, 0, -1, 0, -1, 1, 1, -1};
const vi dx = {0, 1, 0, -1, -1, 1, -1, 1};

#ifdef DEBUG
#define DBG if(1)
#else
#define DBG if(0)
#endif

#define dbg(x) cout << "(" << #x << " : " << x << ")" << endl;
// ostreams
template <class T, class U>
ostream& operator<<(ostream& out, const pair<T, U> &par) {out << "[" << par.first << ";" << par.second << "]"; return out;}
template <class T>
ostream& operator<<(ostream& out, const set<T> &cont) { out << "{"; for( const auto &x:cont) out << x << ", "; out << "}"; return out; }
template <class T, class U>
ostream& operator<<(ostream& out, const map<T, U> &cont) {out << "{"; for( const auto &x:cont) out << x << ", "; out << "}"; return out; }
template<class T>
ostream& operator<<(ostream& out, const vector<T> &v){ out << "[";  REP(i, v.size()) out << v[i] << ", ";  out << "]"; return out;}
// istreams
template<class T>
istream& operator>>(istream& in, vector<T> &v){ for(auto &x : v) in >> x; return in; }
template<class T, class U>
istream& operator>>(istream& in, pair<T, U> &p){ in >> p.ff >> p.ss; return in; }
//searches
template<typename T, typename U>
T bsl(T lo, T hi, U f){ hi++; T mid; while(lo < hi){ mid = (lo + hi)/2; f(mid) ? hi = mid : lo = mid+1; } return lo; }
template<typename U>
double bsld(double lo, double hi, U f, double p = 1e-9){ int r = 3 + (int)log2((hi - lo)/p); double mid; while(r--){ mid = (lo + hi)/2; f(mid) ? hi = mid : lo = mid; } return (lo + hi)/2; }
template<typename T, typename U>
T bsh(T lo, T hi, U f){ lo--; T mid; while(lo < hi){ mid = (lo + hi + 1)/2; f(mid) ? lo = mid : hi = mid-1; } return lo; }
template<typename U>
double bshd(double lo, double hi, U f, double p = 1e-9){ int r = 3+(int)log2((hi - lo)/p); double mid; while(r--){ mid = (lo + hi)/2; f(mid) ? lo = mid : hi = mid; } return (lo + hi)/2; }
// some more utility functions
template<typename T>
pair<T, int> get_min(vector<T> &v){ typename vector<T> :: iterator it = min_element(v.begin(), v.end()); return mp(*it, it - v.begin());}
template<typename T>
pair<T, int> get_max(vector<T> &v){ typename vector<T> :: iterator it = max_element(v.begin(), v.end()); return mp(*it, it - v.begin());}        
template<typename T> bool ckmin(T& a, const T& b){return b < a ? a = b , true : false;}
template<typename T> bool ckmax(T& a, const T& b){return b > a ? a = b, true : false;}

    
int main(){
 	ios_base::sync_with_stdio(false);
 	cin.tie(NULL); cout.tie(NULL);
	int n, s, q, e;
    cin >> n >> s >> q >> e;
    e--; 
    vector<vector<array<int, 2>>> g(n);
    vector<array<int, 2>> edges(n - 1);
    REP(i, n - 1){
        int a, b, w;
        cin >> a >> b >> w;
        a--; b--;
        g[a].pb({b, w});
        g[b].pb({a, w});
        edges[i] = {a, b};
    }
    vector<bool> is_shop(n, false);
    REP(i, s){
        int x; cin >> x;
        x--;
        is_shop[x] = true;
    }
    vll opt(n, INFF);
    function<void(int, int)> calc_opt = [&](int v, int p){
        for(auto x : g[v]){
            if(x[0] == p) continue;
            calc_opt(x[0], v);
        }
        if(is_shop[v]) opt[v] = 0;
        for(auto x : g[v]){
            if(x[0] == p) continue;
            opt[v] = min(opt[v], opt[x[0]] + x[1]);
        }
    };
    calc_opt(e, -1);
    vi lev(n, 0);
    vll dist(n, 0);
    const int mxn = 20;
    vector<vi> nxt(n, vi(mxn, -1));
    vector<vll> nxt_values(n, vll(mxn, INFF));
    function<void(int, int)> dfs = [&](int v, int p){
        nxt[v][0] = p;
        if(p != -1)
            nxt_values[v][0] = opt[v] - dist[v];
        FOR(i, 1, mxn, 1){
            if(nxt[v][i - 1] != -1){
                nxt[v][i] = nxt[nxt[v][i - 1]][i - 1]; 
                nxt_values[v][i] = min(nxt_values[v][i - 1], nxt_values[nxt[v][i - 1]][i - 1]);
            }
        }
        for(auto x : g[v]){
            if(x[0] == p) continue;
            dist[x[0]] = dist[v] + x[1];
            lev[x[0]] = lev[v] + 1;
            dfs(x[0], v);
        }
    };
    dfs(e, -1);
    REP(qq, q){
        int i, r; 
        cin >> i >> r;
        i--; r--;
        int u = edges[i][0]; 
        int v = edges[i][1];
        if(lev[u] < lev[v]) swap(u, v);
        int X = r;
        REPD(j, 19){
            if(lev[X] - (1 << j) >= lev[u]){
                X = nxt[X][j];
            }
        }
        if(X != u){
            cout << "escaped" << "\n";
            continue;
        }
        // now u is ancestor of r;
        // use precomputed binlifts of value opt[x] - dist(E, x);
        X = r;
        ll ans = INFF;
        REPD(j, 19){
            if(lev[X] - (1 << j) >= lev[u]){
                ans = min(ans, nxt_values[X][j] + dist[r]);
                X = nxt[X][j]; 
            }
        }
        ans = min(ans, nxt_values[X][0] + dist[r]);
        if(ans == INFF){
            cout << "oo" << "\n";
        }
        else{
            cout << ans << "\n";
        }
    }
    return 0;
}

Subtask #1
9.0 / 9.0

# 결과 실행 시간 메모리 Grader output
1 Correct 4 ms 492 KB Output is correct
2 Correct 6 ms 512 KB Output is correct
3 Correct 4 ms 632 KB Output is correct
4 Correct 4 ms 492 KB Output is correct

Subtask #2
27.0 / 27.0

# 결과 실행 시간 메모리 Grader output
1 Correct 4 ms 492 KB Output is correct
2 Correct 6 ms 512 KB Output is correct
3 Correct 4 ms 632 KB Output is correct
4 Correct 4 ms 492 KB Output is correct
5 Correct 2 ms 748 KB Output is correct
6 Correct 2 ms 748 KB Output is correct
7 Correct 2 ms 748 KB Output is correct
8 Correct 2 ms 748 KB Output is correct
9 Correct 2 ms 748 KB Output is correct
10 Correct 3 ms 748 KB Output is correct
11 Correct 2 ms 748 KB Output is correct
12 Correct 3 ms 748 KB Output is correct
13 Correct 2 ms 876 KB Output is correct
14 Correct 2 ms 876 KB Output is correct

Subtask #3
23.0 / 23.0

# 결과 실행 시간 메모리 Grader output
1 Correct 210 ms 45164 KB Output is correct
2 Correct 248 ms 45040 KB Output is correct
3 Correct 274 ms 44908 KB Output is correct
4 Correct 328 ms 47072 KB Output is correct
5 Correct 337 ms 47212 KB Output is correct
6 Correct 472 ms 49388 KB Output is correct

Subtask #4
41.0 / 41.0

# 결과 실행 시간 메모리 Grader output
1 Correct 4 ms 492 KB Output is correct
2 Correct 6 ms 512 KB Output is correct
3 Correct 4 ms 632 KB Output is correct
4 Correct 4 ms 492 KB Output is correct
5 Correct 2 ms 748 KB Output is correct
6 Correct 2 ms 748 KB Output is correct
7 Correct 2 ms 748 KB Output is correct
8 Correct 2 ms 748 KB Output is correct
9 Correct 2 ms 748 KB Output is correct
10 Correct 3 ms 748 KB Output is correct
11 Correct 2 ms 748 KB Output is correct
12 Correct 3 ms 748 KB Output is correct
13 Correct 2 ms 876 KB Output is correct
14 Correct 2 ms 876 KB Output is correct
15 Correct 210 ms 45164 KB Output is correct
16 Correct 248 ms 45040 KB Output is correct
17 Correct 274 ms 44908 KB Output is correct
18 Correct 328 ms 47072 KB Output is correct
19 Correct 337 ms 47212 KB Output is correct
20 Correct 472 ms 49388 KB Output is correct
21 Correct 203 ms 44808 KB Output is correct
22 Correct 232 ms 44524 KB Output is correct
23 Correct 259 ms 44268 KB Output is correct
24 Correct 320 ms 46828 KB Output is correct
25 Correct 432 ms 50028 KB Output is correct
26 Correct 201 ms 44652 KB Output is correct
27 Correct 235 ms 44396 KB Output is correct
28 Correct 254 ms 44268 KB Output is correct
29 Correct 340 ms 45932 KB Output is correct
30 Correct 465 ms 47724 KB Output is correct
31 Correct 213 ms 44744 KB Output is correct
32 Correct 258 ms 44396 KB Output is correct
33 Correct 282 ms 44512 KB Output is correct
34 Correct 346 ms 46828 KB Output is correct
35 Correct 454 ms 49900 KB Output is correct
36 Correct 325 ms 46956 KB Output is correct