Submission #119779

#	Time	Username	Problem	Language	Result	Execution time	Memory
119779		ahmad_salah	Parachute rings (IOI12_rings)	C++17	20 / 100	4090 ms	41204 KiB

rings

#include <bits/stdc++.h>

using namespace std;

const int M = 1e6;
int n, endss;
vector<int> adj[M];
bool v[M], ok;

void dfs(int node, int forb) {
    if (!v[node]) {
        v[node] = 1;

        int cnt = 0;
        for (int x : adj[node])
            if (x != forb)
                cnt++;

        if (cnt > 2) {
            ok = false;
            return;
        }

        if (!cnt)
            endss = 2;
        else if (cnt == 1)
            endss++;

        for (int x : adj[node])
            if (x != forb)
                dfs(x, forb);
    }
}

void Init(int N) { n = N; }

void Link(int a, int b) {
    adj[a].push_back(b);
    adj[b].push_back(a);
}

int CountCritical() {
    int ans = 0;

    for (int i = 0; i < n; i++) {
        memset(v, 0, sizeof v);
        ok = true;

        for (int j = 0; j < n; j++)
            if (!v[j] && i != j) {
                endss = 0;
                dfs(j, i);
                if (endss != 2)
                    ok = false;
            }

        ans += ok;
    }

    return ans;
}

• Subtask 1: 20 / 20
• Subtask 2: 0 / 17
• Subtask 3: 0 / 18
• Subtask 4: 0 / 14
• Subtask 5: 0 / 31