Submission #531168

#	Time	Username	Problem	Language	Result	Execution time	Memory
531168		4fecta	Bitaro’s Party (JOI18_bitaro)	C++17	100 / 100	1664 ms	255892 KiB

bitaro

#include <bits/stdc++.h>
using namespace std;
#define ll long long
#define int ll
#define ld long double
#define pii pair<int, int>
#define f first
#define s second
#define boost() cin.tie(0), cin.sync_with_stdio(0)

const int MN = 200005, BLK = 50;

int n, m, q, u, v, k, dp[MN], s[MN], rem[MN];
vector<int> a[MN], r[MN];
vector<pii> far[MN];

bool cmp(pii p, pii q) {
    if (p.s != q.s) return p.s < q.s;
    return p.f > q.f;
}

int32_t main() {
    boost();

    cin >> n >> m >> q;
    for (int i = 1; i <= m; i++) {
        cin >> u >> v;
        a[u].push_back(v);
        r[v].push_back(u);
    }
    for (int i = 1; i <= n; i++) {
        far[i].push_back({0, i});
        for (int j : r[i]) for (pii p : far[j]) far[i].push_back({p.f + 1, p.s});
        sort(far[i].begin(), far[i].end(), cmp);
        vector<pii> tmp;
        int pre = -1;
        for (pii p : far[i]) if (p.s != pre) {pre = p.s; tmp.push_back(p);}
        far[i] = tmp;
        sort(far[i].begin(), far[i].end(), greater<>());
        while (far[i].size() > BLK) far[i].pop_back();
    }
    for (int i = 1; i <= q; i++) {
        cin >> u >> k;
        for (int j = 1; j <= k; j++) cin >> rem[j], s[rem[j]] = 1;
        if (k >= BLK) {
            for (int j = 1; j <= u; j++) {
                if (!s[j]) dp[j] = 0;
                else dp[j] = -1;
                for (int p : r[j]) if (dp[p] != -1) dp[j] = max(dp[j], dp[p] + 1);
            }
            printf("%lld\n", dp[u]);
        } else {
            int ans = -1;
            for (pii p : far[u]) if (!s[p.s]) {ans = p.f; break;}
            printf("%lld\n", ans);
        }
        for (int j = 1; j <= k; j++) s[rem[j]] = 0;
    }

    return 0;
}

• Subtask 1: 7 / 7
• Subtask 2: 7 / 7
• Subtask 3: 86 / 86