Submission #653863

#	Time	Username	Problem	Language	Result	Execution time	Memory
653863		longvu	KOVANICE (COI15_kovanice)	C++14	0 / 100	190 ms	39012 KiB

kovanice

/**
 *    author:  longvu
 *    created: 10/28/22 21:23:23
**/
#include<bits/stdc++.h>

using namespace std;

#define int long long
#define sz(x) ((int)x.size())
#define all(x) (x).begin(), (x).end()
const int INF = numeric_limits<int>::max();
const int nax = (int)(390001);
const int mod = 1e9 + 7;

template<class X, class Y>
bool maximize(X& x, const Y y) {
    if (y > x) {x = y; return true;}
    return false;
}
template<class X, class Y>
bool minimize(X& x, const Y y) {
    if (y < x) {x = y; return true;}
    return false;
}

struct DSU {
    int pa[nax], color[nax];
    DSU(int n) {
        for (int i = 1; i <= n; ++i) {
            pa[i] = i;
            color[i] = 0;
        }
    }

    int find(int u) {
        return pa[u] = ((u != pa[u]) ? find(pa[u]) : pa[u]);
    }

    bool join(int u, int v) {
        u = find(u), v = find(v);
        if (u == v) return false;
        if (v < u) {
            swap(u, v);
        }
        pa[v] = u;
        return true;
    }
};

int U[nax], T[nax], V[nax], vis[nax], ans[nax];
vector<int> adj[nax];
int32_t main() {
    ios_base::sync_with_stdio(false);
    cin.tie(0);
    int n, m, k;
    cin >> n >> m >> k;
    for (int i = 1; i <= k; ++i) {
        string s;
        cin >> s;
        int j = 0;
        while (s[j] >= '0' && s[j] <= '9') {
            U[i] = 10 * U[i] + (s[j] - '0');
            j++;
        }
        if (s[j] == '<') {
            T[i] = 0;
        }
        if (s[j] == '>') {
            T[i] = 1;
        }
        if (s[j] == '=') {
            T[i] = 2;
        }
        j++;
        while (j < sz(s)) {
            V[i] = 10 * V[i] + (s[j] - '0');
            j++;
        }
    }
    for (int i = 1; i <= k; ++i) {
        // cout << U[i] << " " << V[i] << " " << T[i] << '\n';
        if (!T[i]) {
            adj[U[i]].push_back(V[i]);
        }
        if (T[i]) {
            adj[V[i]].push_back(U[i]);
        }
    }
    function<bool(int, int)> dfs = [&](int u, int d) {
        vis[u] = 1;
        if (d == n) {
            ans[u] = d;
            return true;
        }
        bool ok = 0;
        for (auto v : adj[u]) {
            if (!vis[v]) {
                ok |= dfs(v, d + 1);
            }
        }
        if (ok) {
            ans[u] = d;
        }
        return ok;
    };
    for (int i = 1; i <= m; ++i) {
        if (!vis[i]) {
            dfs(i, 1);
        }
    }
    for (int i = 1; i <= k; ++i) {
        if (T[i] == 2) {
            if (ans[U[i]]) {
                ans[V[i]] = ans[U[i]];
            } else {
                ans[U[i]] = ans[V[i]];
            }
        }
    }
    DSU dsu(m);
    for (int i = 1; i <= k; ++i) {
        if (T[i] == 2) {
            dsu.join(U[i], V[i]);
        }
    }
    for (int i = 1; i <= m; ++i) {
        if (ans[i]) {
            dsu.color[dsu.find(i)] = ans[i];
        }
    }
    for (int i = 1; i <= m; ++i) {
        if (dsu.color[dsu.find(i)]) {
            cout << "K" << dsu.color[dsu.find(i)] << '\n';
        } else {
            cout << "?" << '\n';
        }
    }
    return 0;
}

• Subtask 1: 0 / 10
• Subtask 2: 0 / 40
• Subtask 3: 0 / 10
• Subtask 4: 0 / 40