oj.uz

Submission #851388

# Submission time Handle Problem Language Result Execution time Memory
851388 2023-09-19T17:23:23 Z EJIC_B_KEDAX Jail (JOI22_jail) C++14
0 / 100
 10 ms 604 KB 
#include <bits/stdc++.h>
#include <random>

#ifndef LOCAL
//#pragma GCC optimize("O3")
//#pragma GCC optimize("Ofast")
//#pragma GCC optimize("unroll-loops")
//#pragma GCC target("avx,avx2,bmi,bmi2,popcnt,lzcnt")
#endif
using namespace std;
typedef long long ll;
typedef double dd;
typedef long double ld;
typedef unsigned int uii;
#define x first
#define y second
#define all(x) x.begin(), x.end()
#define rall(x) x.rbegin(), x.rend()


void solve();

mt19937_64 mt(1);

int32_t main() {
#ifdef LOCAL
    freopen("input.in", "r", stdin);
    freopen("output.out", "w", stdout);
#else
    ios::sync_with_stdio(false);
    cin.tie(nullptr); cout.tie(nullptr);
    //freopen("amusing.in", "r", stdin);
    //freopen("amusing.out", "w", stdout);
#endif
    cout << fixed << setprecision(30);
    int tests = 1;
    cin >> tests;
    while (tests--) {
        solve();
    }
}

int tim = 0;

void dfs(int s, int p, vector<vector<int>>& g, vector<int>& tin, vector<int>& tout, vector<int>& pr) {
    tin[s] = tim++;
    pr[s] = p;
    for (int i : g[s]) {
        if (i != p) {
            dfs(i, s, g, tin, tout, pr);
        }
    }
    tout[s] = tim++;
}

bool a_p_b(int a, int b, vector<int>& tin, vector<int>& tout) {
    return tin[a] <= tin[b] && tout[a] >= tout[b];
}

struct path {
    int u, v, lca;
};

void solve() {
    tim = 0;
    int n;
    cin >> n;
    vector<vector<int>> g(n);
    for (int i = 0; i < n - 1; i++) {
        int u, v;
        cin >> u >> v; v--; u--;
        g[v].push_back(u);
        g[u].push_back(v);
    }
    vector<int> s(n, -1), t(n, -1), tin(n), tout(n), pr(n), cnt(n, 0);
    dfs(0, -1, g, tin, tout, pr);
    int q, sc = 0;
    cin >> q;
    bool ans = true;
    vector<int> u;
    vector<path> z;
    while (q--) {
        int a, b;
        cin >> a >> b; a--; b--;
        if (!ans) {
            continue;
        }
        z.push_back({a, b, 0});
        int a1 = a, b1 = b;
        while (!a_p_b(a1, b, tin, tout)) {
            if (s[a1] != -1) {
                cnt[s[a1]] += 2;
                u.push_back(s[a1]);
            }
            if (t[a1] != -1) {
                cnt[t[a1]]++;
                u.push_back(t[a1]);
            }
            a1 = pr[a1];
        }
        while (!a_p_b(b1, a, tin, tout)) {
            if (s[b1] != -1) {
                cnt[s[b1]] += 2;
                u.push_back(s[b1]);
            }
            if (t[b1] != -1) {
                cnt[t[b1]]++;
                u.push_back(t[b1]);
            }
            b1 = pr[b1];
        }
        if (s[b1] != -1) {
            cnt[s[b1]] += 2;
            u.push_back(s[b1]);
        }
        if (t[b1] != -1) {
            cnt[t[b1]]++;
            u.push_back(t[b1]);
        }
        z[z.size() - 1].lca = a1;
        s[a] = sc;
        t[b] = sc++;
        for (int i : u) {
            if (!cnt[i]) {
                continue;
            }
            if (cnt[i] == 1 && a_p_b(a1, z[i].v, tin, tout) && (a_p_b(z[i].v, a, tin, tout) || a_p_b(z[i].v, b, tin, tout)) && a_p_b(z[i].lca, b, tin, tout) && (a_p_b(b, z[i].u, tin, tout) || a_p_b(b, z[i].v, tin, tout))) {
                ans = false;
            }
            if (cnt[i] > 2) {
                ans = false;
            }
            cnt[i] = 0;
        }
        u.clear();
    }
    if (ans) {
        cout << "Yes\n";
    } else {
        cout << "No\n";
    }
}

Subtask #1
0 / 5.0

# Verdict Execution time Memory Grader output
1 Correct 1 ms 344 KB Output is correct
2 Correct 0 ms 348 KB Output is correct
3 Correct 0 ms 348 KB Output is correct
4 Incorrect 10 ms 604 KB Output isn't correct
5 Halted 0 ms 0 KB -

Subtask #2
0 / 5.0

# Verdict Execution time Memory Grader output
1 Correct 1 ms 348 KB Output is correct
2 Correct 1 ms 460 KB Output is correct
3 Incorrect 1 ms 468 KB Output isn't correct
4 Halted 0 ms 0 KB -

Subtask #3
0 / 16.0

# Verdict Execution time Memory Grader output
1 Correct 1 ms 348 KB Output is correct
2 Correct 1 ms 460 KB Output is correct
3 Incorrect 1 ms 468 KB Output isn't correct
4 Halted 0 ms 0 KB -

Subtask #4
0 / 28.0

# Verdict Execution time Memory Grader output
1 Correct 1 ms 348 KB Output is correct
2 Correct 1 ms 460 KB Output is correct
3 Incorrect 1 ms 468 KB Output isn't correct
4 Halted 0 ms 0 KB -

Subtask #5
0 / 12.0

# Verdict Execution time Memory Grader output
1 Correct 1 ms 348 KB Output is correct
2 Correct 1 ms 460 KB Output is correct
3 Incorrect 1 ms 468 KB Output isn't correct
4 Halted 0 ms 0 KB -

Subtask #6
0 / 11.0

# Verdict Execution time Memory Grader output
1 Correct 1 ms 344 KB Output is correct
2 Incorrect 1 ms 344 KB Output isn't correct
3 Halted 0 ms 0 KB -

Subtask #7
0 / 23.0

# Verdict Execution time Memory Grader output
1 Correct 1 ms 344 KB Output is correct
2 Correct 0 ms 348 KB Output is correct
3 Correct 0 ms 348 KB Output is correct
4 Incorrect 10 ms 604 KB Output isn't correct
5 Halted 0 ms 0 KB -