Submission #1124473

#	Time	Username	Problem	Language	Result	Execution time	Memory
1124473		Yang8on	Bitaro’s Party (JOI18_bitaro)	C++20	100 / 100	667 ms	111408 KiB

bitaro

#include <bits/stdc++.h>
#define Y8o "bitaro"
#define maxn (int) 1e5 + 5
#define ll long long
#define pii pair<int, int>
#define gb(i, j) ((i >> j) & 1)
#define all(x) x.begin(), x.end()
#define _left id * 2, l, mid
#define _right id * 2 + 1, mid + 1, r
#define fi(i, a, b) for(int i = a; i <= b; i ++)
#define fid(i, a, b) for(int i = a; i >= b; i --)

//#define f first
//#define s second

using namespace std;

mt19937_64 rng(chrono::steady_clock::now().time_since_epoch().count());
ll GetRandom(ll l, ll r) {
    return uniform_int_distribution<ll> (l, r) (rng);
}
void iof() {
    ios_base::sync_with_stdio(0);
    cin.tie(NULL), cout.tie(NULL);
    if(fopen(Y8o".inp", "r"))
    {
        freopen(Y8o".inp", "r", stdin);
//        freopen(Y8o".out", "w", stdout);
    }
}
void ctime() {
    cerr << "\n" << "\nTime elapsed: " << 1000 * clock() / CLOCKS_PER_SEC << "ms\n";
}

const int inf = 1e9;
const int can = 100;

int n, m, Q;
vector<int> o[maxn];
int a[maxn], dp2[maxn];
int dd[maxn], mx[maxn];
vector<pii> dp[maxn];


void solve() {
    cin >> n >> m >> Q;
    fi(i, 1, m) {
        int u, v; cin >> u >> v;
        o[v].push_back(u);
    }

    fi(u, 1, n) {
        vector<int> tmp;
        tmp.push_back(u), mx[u] = 0;
        for(int ke : o[u]) for(auto [x, v] : dp[ke]) {
            if(dd[v] == u) mx[v] = max(mx[v], x + 1);
            else dd[v] = u, mx[v] = x + 1, tmp.push_back(v);
        }
        sort( all(tmp), [](int x, int y) { return mx[x] < mx[y]; });
        while(dp[u].size() < can && tmp.size()) {
            dp[u].push_back({ mx[tmp.back()], tmp.back() });
            tmp.pop_back();
        }
    }

    fi(i ,1, n) dd[i] = 0;

    fi(_, 1, Q) {
        int root, k; cin >> root >> k ;
        fi(i, 1, k) cin >> a[i], dd[ a[i] ] = 1;

        if(k >= can) {
             fi(i, 1, n) {
                dp2[i] = 0;
                if(dd[i]) dp2[i] = -inf;
            }
            fi(u, 1, root) {
                for(int v : o[u]) {
                    dp2[u] = max(dp2[u], dp2[v] + 1);
                }
            }
            cout << (dp2[root] < 0 ? -1 : dp2[root]) << '\n';
        }
        else {
            int ans = dd[root] ? -inf : 0;
            for(auto [x, v] : dp[root]) {
                if(!dd[v]) { ans = x; break; }
            }
            cout << (ans < 0 ? -1 : ans) << '\n';
        }

        fi(i, 1, k) dd[ a[i] ] = 0;
    }
}

int main() {
    iof();

    int nTest = 1;
//    cin >> nTest;

    while(nTest --) {
        solve();
    }

    ctime();
    return 0;
}

Compilation message (stderr)

bitaro.cpp: In function 'void iof()':
bitaro.cpp:27:16: warning: ignoring return value of 'FILE* freopen(const char*, const char*, FILE*)' declared with attribute 'warn_unused_result' [-Wunused-result]
   27 |         freopen(Y8o".inp", "r", stdin);
      |         ~~~~~~~^~~~~~~~~~~~~~~~~~~~~~~

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