oj.uz

Submission #679254

# Submission time Handle Problem Language Result Execution time Memory
679254 2023-01-07T23:28:38 Z stevancv Valley (BOI19_valley) C++14
100 / 100
 212 ms 42604 KB 
#include <bits/stdc++.h>
#define ll long long
#define ld long double
#define sp ' '
#define en '\n'
#define smin(a, b) a = min(a, b)
#define smax(a, b) a = max(a, b)
using namespace std;
const int N = 1e5 + 2;
const int mod = 1e9 + 7;
const ll linf = 1e18;
int par[N][17];
ll mn[N][17];
int main() {
    ios::sync_with_stdio(false);
    cin.tie(0);
    cout.tie(0);
    int n, s, q, e;
    cin >> n >> s >> q >> e;
    e -= 1;
    vector<int> u(n), v(n), w(n);
    vector<vector<array<int, 2>>> g(n);
    for (int i = 0; i < n - 1; i++) {
        cin >> u[i] >> v[i] >> w[i];
        u[i] -= 1; v[i] -= 1;
        g[u[i]].push_back({v[i], i});
        g[v[i]].push_back({u[i], i});
    }
    vector<bool> is(n);
    for (int i = 0; i < s; i++) {
        int x; cin >> x; x -= 1;
        is[x] = 1;
    }
    vector<int> in(n), out(n), dep(n);
    int tsz = -1;
    vector<ll> opt(n, linf), pref(n);
    function<void(int, int, ll)> Dfs = [&] (int s, int e, ll o) {
        in[s] = ++tsz;
        pref[s] = o;
        par[s][0] = e;
        for (int i = 1; i < 17; i++) {
            if (par[s][i - 1] != -1) par[s][i] = par[par[s][i - 1]][i - 1];
            else par[s][i] = -1;
        }
        for (auto u : g[s]) {
            if (u[0] == e) continue;
            dep[u[0]] = dep[s] + 1;
            Dfs(u[0], s, o + w[u[1]]);
            smin(opt[s], opt[u[0]] + w[u[1]]);
        }
        if (is[s] == 1) opt[s] = 0;
        out[s] = tsz;
    };
    Dfs(e, -1, 0);
    for (int i = 0; i < n - 1; i++) {
        if (in[u[i]] > in[v[i]]) swap(u[i], v[i]);
    }
    for (int i = 0; i < n; i++) {
        if (opt[i] != linf) opt[i] -= pref[i];
    }
    function<void(int, int)> Dfs1 = [&] (int s, int e) {
        mn[s][0] = opt[s];
        for (int i = 1; i < 17; i++) {
            mn[s][i] = mn[s][i - 1];
            if (par[s][i - 1] != -1) smin(mn[s][i], mn[par[s][i - 1]][i - 1]);
        }
        for (auto u : g[s]) {
            if (u[0] == e) continue;
            Dfs1(u[0], s);
        }
    };
    Dfs1(e, -1);
    auto Get = [&] (int l, int r) {
        int kol = dep[r] - dep[l];
        ll ans = linf;
        for (int i = 16; i >= 0; i--) {
            if ((1 << i) & kol) {
                smin(ans, mn[r][i]);
                r = par[r][i];
            }
        }
        return min(opt[l], ans);
    };
    while (q--) {
        int x, y;
        cin >> x >> y;
         x -= 1; y -= 1;
         if (!(in[v[x]] <= in[y] && out[y] <= out[v[x]])) {
            cout << "escaped" << en;
            continue;
         }
         if (opt[v[x]] == linf) {
            cout << "oo" << en;
            continue;
         }
         ll ans = pref[y] + Get(v[x], y);
         cout << ans << en;
    }
    return 0;
}

Subtask #1
9.0 / 9.0

# Verdict Execution time Memory Grader output
1 Correct 3 ms 468 KB Output is correct
2 Correct 3 ms 468 KB Output is correct
3 Correct 3 ms 468 KB Output is correct
4 Correct 3 ms 464 KB Output is correct

Subtask #2
27.0 / 27.0

# Verdict Execution time Memory Grader output
1 Correct 3 ms 468 KB Output is correct
2 Correct 3 ms 468 KB Output is correct
3 Correct 3 ms 468 KB Output is correct
4 Correct 3 ms 464 KB Output is correct
5 Correct 1 ms 596 KB Output is correct
6 Correct 1 ms 596 KB Output is correct
7 Correct 1 ms 596 KB Output is correct
8 Correct 1 ms 596 KB Output is correct
9 Correct 1 ms 596 KB Output is correct
10 Correct 1 ms 596 KB Output is correct
11 Correct 2 ms 600 KB Output is correct
12 Correct 1 ms 596 KB Output is correct
13 Correct 1 ms 596 KB Output is correct
14 Correct 1 ms 672 KB Output is correct

Subtask #3
23.0 / 23.0

# Verdict Execution time Memory Grader output
1 Correct 159 ms 34992 KB Output is correct
2 Correct 145 ms 34608 KB Output is correct
3 Correct 155 ms 34504 KB Output is correct
4 Correct 212 ms 37772 KB Output is correct
5 Correct 159 ms 37780 KB Output is correct
6 Correct 181 ms 41472 KB Output is correct

Subtask #4
41.0 / 41.0

# Verdict Execution time Memory Grader output
1 Correct 3 ms 468 KB Output is correct
2 Correct 3 ms 468 KB Output is correct
3 Correct 3 ms 468 KB Output is correct
4 Correct 3 ms 464 KB Output is correct
5 Correct 1 ms 596 KB Output is correct
6 Correct 1 ms 596 KB Output is correct
7 Correct 1 ms 596 KB Output is correct
8 Correct 1 ms 596 KB Output is correct
9 Correct 1 ms 596 KB Output is correct
10 Correct 1 ms 596 KB Output is correct
11 Correct 2 ms 600 KB Output is correct
12 Correct 1 ms 596 KB Output is correct
13 Correct 1 ms 596 KB Output is correct
14 Correct 1 ms 672 KB Output is correct
15 Correct 159 ms 34992 KB Output is correct
16 Correct 145 ms 34608 KB Output is correct
17 Correct 155 ms 34504 KB Output is correct
18 Correct 212 ms 37772 KB Output is correct
19 Correct 159 ms 37780 KB Output is correct
20 Correct 181 ms 41472 KB Output is correct
21 Correct 124 ms 34356 KB Output is correct
22 Correct 133 ms 34056 KB Output is correct
23 Correct 159 ms 34036 KB Output is correct
24 Correct 154 ms 37784 KB Output is correct
25 Correct 173 ms 42604 KB Output is correct
26 Correct 147 ms 34532 KB Output is correct
27 Correct 125 ms 34004 KB Output is correct
28 Correct 135 ms 34064 KB Output is correct
29 Correct 174 ms 36424 KB Output is correct
30 Correct 185 ms 38964 KB Output is correct
31 Correct 133 ms 34472 KB Output is correct
32 Correct 140 ms 34188 KB Output is correct
33 Correct 143 ms 34240 KB Output is correct
34 Correct 175 ms 37428 KB Output is correct
35 Correct 175 ms 42360 KB Output is correct
36 Correct 169 ms 37708 KB Output is correct