Submission #397731

#	Time	Username	Problem	Language	Result	Execution time	Memory
397731		KoD	Paths (BOI18_paths)	C++17	100 / 100	733 ms	70768 KiB

paths

#include <bits/stdc++.h>

using ll = long long;

template <class T>
using Vec = std::vector<T>;

int main() {
    int N, M, K;
    std::cin >> N >> M >> K;
    Vec<int> col(N);
    for (auto& x: col) {
        std::cin >> x;
        x -= 1;
    }
    Vec<Vec<int>> graph(N);
    for (int i = 0; i < M; ++i) {
        int a, b;
        std::cin >> a >> b;
        a -= 1;
        b -= 1;
        graph[a].push_back(b);
        graph[b].push_back(a);
    }
    Vec<Vec<ll>> count(N, Vec<ll>(1 << K));
    for (int i = 0; i < N; ++i) {
        count[i][1 << col[i]] += 1;
    }
    for (int set = 0; set < (1 << K); ++set) {
        for (int i = 0; i < N; ++i) {
            if (!(set >> col[i] & 1)) {
                continue;
            }
            for (const auto j: graph[i]) {
                count[i][set] += count[j][set & ~(1 << col[i])];
            }
        }
    }
    ll ans = 0;
    for (int i = 0; i < N; ++i) {
        for (int j = 0; j < (1 << K); ++j) {
            if (__builtin_popcount(j) >= 2) {
                ans += count[i][j];               
            }
        }
    }
    std::cout << ans << '\n';
    return 0;
}

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