제출 #1140247

#	제출 시각	아이디	문제	언어	결과	실행 시간	메모리
1140247		Persia	수도 (JOI20_capital_city)	C++17	1 / 100	197 ms	14408 KiB

capital_city

#include <bits/stdc++.h>
#define bit(i, x) (x >> i & 1)
#define ll long long
const int N = 2e5 + 5;
const int mod = 998244353;
using namespace std;

int n, k;
vector<int> c;
vector<vector<int>> G;

int subtask1() {
    vector<int> sz(k + 3, 0);
    vector<int> cnt(k + 3, 0);
    vector<int> vst(n + 3, 0);
    vector<int> mark(n + 3, 0);
    int res = n;

    function<void(int)> dfs = [&](int u) -> void {
        vst[u] = 1;
        for(int v : G[u]) if(!vst[v] && mark[v]) {
            dfs(v);
        }
    };

    for(int i = 1; i <= n; i++) sz[c[i]]++;

    for(int mask = 1; mask < (1 << n); mask++) {
        cnt.assign(k + 3, 0);
        vst.assign(n + 3, 0);
        mark.assign(n + 3, 0);
        int d = 0, s = 0;
        bool flag = 1;

        for(int i = 1; i <= n; i++) if(bit(i - 1, mask)) {
            d += (cnt[c[i]]++ == 0);
            if(s == 0) s = i;
            mark[i] = 1;
        }
        for(int i = 1; i <= n; i++) if(bit(i - 1, mask)) {
            if(cnt[c[i]] != sz[c[i]]) {
                flag = 0;
                break;
            }
        }
        if(flag) {
            bool flag2 = 1;

            dfs(s);
            for(int i = 1; i <= n; i++) if(bit(i - 1, mask)) {
                if(!vst[i]) {
                    flag2 = 0;
                    break;
                }
            }
            if(flag2) res = min(res, d - 1);
        }
    }
    return res;
}

signed main(int argc, char* argv[]) {
    ios_base::sync_with_stdio(0);
    cin.tie(0); cout.tie(0);

    cin >> n >> k;
    G.assign(n + 3, vector<int>(0));
    c.assign(n + 3, 0);
    for(int i = 1; i < n; i++) {
        int x, y; cin >> x >> y;
        G[x].push_back(y);
        G[y].push_back(x);
    }
    for(int i = 1; i <= n; i++) {
        cin >> c[i];
    }

    cout << subtask1();
//    subtask1();

    return 0 ^ 0;
}

• Subtask 1: 1 / 1
• Subtask 2: 0 / 10
• Subtask 3: 0 / 30
• Subtask 4: 0 / 59