Submission #1083477

#	Time	Username	Problem	Language	Result	Execution time	Memory
1083477		lamlamlam	Bosses (BOI16_bosses)	C++17	100 / 100	510 ms	848 KiB

bosses

#include <bits/stdc++.h>
using namespace std;
#define int long long
#define endl '\n'
const int MN = 5005,inf = 1e18;
int n,k,u,ans = inf,h[MN];
vector<int> adj[MN];
int bfs(int x)
{
    for(int i=1; i<=n; i++) h[i] = 0;
    h[x] = 1;
    queue<int> q;
    q.push(x);
    while(!q.empty()){
        int u = q.front();
        q.pop();
        for(auto v:adj[u]){
            if(h[v]!=0) continue;
            h[v] = h[u] + 1;
            q.push(v);
        }
    }
    int res = 0;
    for(int i=1; i<=n; i++) {
        if(h[i]==0) return inf;
        res += h[i];
    }
    return res;
}

signed main()
{
    ios_base::sync_with_stdio(false);
    cin.tie(NULL);
    #define task "sus"
    if(fopen(task".inp","r")){
        freopen(task".inp","r",stdin);
        freopen(task".out","w",stdout);
    }
    cin >> n;
    for(int i=1; i<=n; i++){
        cin >> k;
        while(k--){
            cin >> u;
            adj[u].push_back(i);
        }
    }
    for(int i=1; i<=n; i++) ans = min(ans,bfs(i));
    cout << ans;
    cerr << "\nTime: " << clock();
}

Compilation message (stderr)

bosses.cpp: In function 'int main()':
bosses.cpp:37:16: warning: ignoring return value of 'FILE* freopen(const char*, const char*, FILE*)' declared with attribute 'warn_unused_result' [-Wunused-result]
   37 |         freopen(task".inp","r",stdin);
      |         ~~~~~~~^~~~~~~~~~~~~~~~~~~~~~
bosses.cpp:38:16: warning: ignoring return value of 'FILE* freopen(const char*, const char*, FILE*)' declared with attribute 'warn_unused_result' [-Wunused-result]
   38 |         freopen(task".out","w",stdout);
      |         ~~~~~~~^~~~~~~~~~~~~~~~~~~~~~~

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