Submission #617875

#	Time	Username	Problem	Language	Result	Execution time	Memory
617875		sokratisi	Keys (IOI21_keys)	C++17	20 / 100	3066 ms	17092 KiB

keys

#include <vector>
#include <unordered_set>

using namespace std;

int solve(vector<int> r, vector<int> u, vector<int> v, vector<int> c, int s) {
    unordered_set<int> vis;
    unordered_set<int> keys;
    vis.insert(s);
    keys.insert(r[s]);
    int added = 1;
    int m = u.size();
    while (added) {
        added = 0;
        for (int i = 0; i < m; i++) {
            if (vis.find(u[i]) != vis.end()) {
                if (vis.find(v[i]) == vis.end()) {
                    if (keys.find(c[i]) != keys.end()) {
                        added++;
                        vis.insert(v[i]);
                        keys.insert(r[v[i]]);
                    }
                } 
            }
        }
        for (int i = 0; i < m; i++) {
            if (vis.find(v[i]) != vis.end()) {
                if (vis.find(u[i]) == vis.end()) {
                    if (keys.find(c[i]) != keys.end()) {
                        added++;
                        vis.insert(u[i]);
                        keys.insert(r[u[i]]);
                    }
                } 
            }
        }
    }
    return vis.size();
}

vector<int> find_reachable(vector<int> r, vector<int> u, vector<int> v, vector<int> c) {
    int n = r.size();
    vector<int> canreach(n);
    for (int i = 0; i < n; i++) {
        canreach[i] = solve(r, u, v, c, i);
        // printf("%d\n", canreach[i]);
    }
    int least = canreach[0];
    for (int i = 1; i < n; i++) least = min(least, canreach[i]);
	vector<int> ans(n, 0);
    for (int i = 0; i < n; i++) if (canreach[i] == least) ans[i] = 1;

	return ans;
}

• Subtask 1: 9 / 9
• Subtask 2: 11 / 11
• Subtask 3: 0 / 17
• Subtask 4: 0 / 30
• Subtask 5: 0 / 33