Submission #1272137

#	Time	Username	Problem	Language	Result	Execution time	Memory
1272137		icebear	Bosses (BOI16_bosses)	C++20	100 / 100	770 ms	748 KiB

bosses

// ~~ icebear ~~
#include <bits/stdc++.h>
using namespace std;

typedef long long ll;
typedef pair<int, int> ii;
typedef pair<int, ii> iii;

template<class T>
    bool minimize(T &a, const T &b) {
        if (a > b) return a = b, true;
        return false;
    }

template<class T>
    bool maximize(T &a, const T &b) {
        if (a < b) return a = b, true;
        return false;
    }

#define FOR(i,a,b) for(int i=(a); i<=(b); ++i)
#define FORR(i,a,b) for(int i=(a); i>=(b); --i)
#define REP(i, n) for(int i=0; i<(n); ++i)
#define RED(i, n) for(int i=(n)-1; i>=0; --i)
#define MASK(i) (1LL << (i))
#define BIT(S, i) (((S) >> (i)) & 1)
#define mp make_pair
#define pb push_back
#define fi first
#define se second
#define all(x) x.begin(), x.end()
#define task "icebear"

const int MOD = 1e9 + 7;
const int inf = 1e9 + 27092008;
const ll INF = 1e18 + 27092008;
const int N = 5000 + 5;
int n;
vector<int> G[N];
bool vis[N];
int dist[N];

void dfs(int u) {
    vis[u] = true;
    for(int v : G[u]) if (!vis[v])
        dfs(v);
}

void bfs(int u) {
    queue<int> q;
    q.push(u);
    dist[u] = 1;
    while(!q.empty()) {
        u = q.front(); q.pop();
        for(int v : G[u]) if (dist[v] == 0) {
            dist[v] = dist[u] + 1;
            q.push(v);
        }
    }
}

void init(void) {
    cin >> n;
    FOR(i, 1, n) {
        int k; cin >> k;
        while(k--) {
            int x; cin >> x;
            G[x].pb(i);
        }
    }
}

void process(void) {
    int ans = inf;
    FOR(i, 1, n) {
        memset(vis, false, sizeof vis);
        dfs(i);
        if (count(vis + 1, vis + n + 1, true) < n) continue;
        memset(dist, 0, sizeof dist);
        bfs(i);
        int sum = 0;
        FOR(j, 1, n) sum += dist[j];
        minimize(ans, sum);
    }
    cout << ans;
}

int main() {
    ios_base::sync_with_stdio(0);
    cin.tie(0); cout.tie(0);
    if (fopen(task".inp", "r")) {
        freopen(task".inp", "r", stdin);
        freopen(task".out", "w", stdout);
    }
    int tc = 1;
//    cin >> tc;
    while(tc--) {
        init();
        process();
    }
    return 0;
}

Compilation message (stderr)

bosses.cpp: In function 'int main()':
bosses.cpp:92:16: warning: ignoring return value of 'FILE* freopen(const char*, const char*, FILE*)' declared with attribute 'warn_unused_result' [-Wunused-result]
   92 |         freopen(task".inp", "r", stdin);
      |         ~~~~~~~^~~~~~~~~~~~~~~~~~~~~~~~
bosses.cpp:93:16: warning: ignoring return value of 'FILE* freopen(const char*, const char*, FILE*)' declared with attribute 'warn_unused_result' [-Wunused-result]
   93 |         freopen(task".out", "w", stdout);
      |         ~~~~~~~^~~~~~~~~~~~~~~~~~~~~~~~~

• Subtask 1: 22 / 22
• Subtask 2: 45 / 45
• Subtask 3: 33 / 33