Submission #341297

#	Time	Username	Problem	Language	Result	Execution time	Memory
341297		AlexNeagu	Bosses (BOI16_bosses)	C++14	67 / 100	1566 ms	1204 KiB

bosses

#include<bits/stdc++.h>
#define int long long
#pragma GCC target ("avx2")
#pragma GCC optimization ("O3")
#pragma GCC optimization ("unroll-loops")
#define pb push_back
#define mp make_pair
using namespace std;
typedef long long ll;
typedef long double ld;
typedef pair<ll,ll> pi;
const int mod = 1e9 + 9;
const int N = 106 * 106;
const int nax = 1e6+6;
mt19937 rng(chrono::steady_clock::now().time_since_epoch().count());
int n, ans = 2e18;
vector<int> possible_childs[5005];
vector<int> cur_tree[5005];
vector<int> dp(5005, 0); 

void dfs(int node, int pre) {
    dp[node] = 1;
    for(auto it : cur_tree[node]) {
        if(it != pre) {
            dfs(it, node);
            dp[node] += dp[it];
        }
    }
}

int root(int x) {
    
    queue<int> Q;
    Q.push(x);
    vector<bool> viz(n + 1, false);
    for(int i = 1; i <= n; i++) {
        cur_tree[i].clear();
        dp[i] = 0;
    }

    viz[x] = true;
    while(Q.size()) {
        int node = Q.front();
        Q.pop();
        for(auto it : possible_childs[node]) {
            if(!viz[it]) {
                viz[it] = true;
                Q.push(it);
                cur_tree[node].push_back(it);
            }
        }
    }
    for(int i = 1; i <= n; i++) if(!viz[i]) return 2e18;
    dfs(x, 0);
    int sol = 0;
    for(int i = 1; i <= n; i++) {
        sol += dp[i];   
    }
    return sol;
}

int32_t main() {
 
    ios_base::sync_with_stdio(false);
    cin.tie(0);

    cin >> n;
    for(int i = 1; i <= n; i++) {
        int len;
        cin >> len;
        for(int j = 1; j <= len; j++) {
            int x;
            cin >> x;
            possible_childs[x].push_back(i);
        }
    }

    for(int i = 1; i <= n; i++) {
        ans = min(ans, root(i));
    }

    cout << ans << '\n';


    return 0;
}

Compilation message (stderr)

bosses.cpp:4: warning: ignoring #pragma GCC optimization [-Wunknown-pragmas]
    4 | #pragma GCC optimization ("O3")
      | 
bosses.cpp:5: warning: ignoring #pragma GCC optimization [-Wunknown-pragmas]
    5 | #pragma GCC optimization ("unroll-loops")
      |

• Subtask 1: 22 / 22
• Subtask 2: 45 / 45
• Subtask 3: 0 / 33