Submission #1084728

#	Time	Username	Problem	Language	Result	Execution time	Memory
1084728		f0rizen	Paths (BOI18_paths)	C++17	100 / 100	219 ms	61268 KiB

paths

#include <bits/stdc++.h>

using namespace std;
using ll = long long;
const int inf = 1e9 + 7;
const ll infll = 1e18;

template<typename T>
istream &operator>>(istream &is, vector<T> &a) {
    for (auto &i : a) {
        is >> i;
    }
    return is;
}

int bit(int mask, int i) {
    return (mask >> i) & 1;
}

int32_t main() {
#ifdef LOCAL
    freopen("/tmp/input.txt", "r", stdin);
#else
    ios::sync_with_stdio(false);
    cin.tie(nullptr);
#endif
    int n, m, k;
    cin >> n >> m >> k;
    vector<int> c(n);
    cin >> c;
    for (auto &i : c) {
        --i;
    }
    vector<vector<int>> g(n);
    for (int i = 0; i < m; ++i) {
        int u, v;
        cin >> u >> v;
        --u, --v;
        g[u].push_back(v);
        g[v].push_back(u);
    }
    vector<vector<ll>> dp(1 << k, vector<ll>(n));
    for (int i = 0; i < n; ++i) {
        dp[1 << c[i]][i] = 1;
    }
    for (int mask = 0; mask < (1 << k); ++mask) {
        for (int i = 0; i < n; ++i) {
            if (!bit(mask, c[i])) {
                continue;
            }
            for (auto j : g[i]) {
                if (!bit(mask, c[j])) {
                    dp[mask ^ (1 << c[j])][j] += dp[mask][i];
                }
            }
        }
    }
    ll sum = 0;
    for (int mask = 0; mask < (1 << k); ++mask) {
        for (int i = 0; i < n; ++i) {
            sum += dp[mask][i];
        }
    }
    cout << sum - n << "\n";
    return 0;
}

• Subtask 1: 23 / 23
• Subtask 2: 20 / 20
• Subtask 3: 27 / 27
• Subtask 4: 30 / 30