답안 #759877

# 제출 시각 아이디 문제 언어 결과 실행 시간 메모리
759877 2023-06-17T01:54:58 Z resting Star Trek (CEOI20_startrek) C++17
100 / 100
281 ms 17184 KB
#include <bits/stdc++.h>
using namespace std;

#define int long long

const int mx = 1e5 + 5;

int sz[mx]{};
int cnt2[mx]{};
int win2[mx]{};
int cnt[mx]{};
int win[mx]{};
bool vis[mx]{};
vector<int> adj[mx]{};

int dfs(int v, int p) {
    if (vis[v]) return 0;
    sz[v] = 1;
    for (auto& x : adj[v])
        if (x != p)
            sz[v] += dfs(x, v);
    return sz[v];
}

void dfs2(int v, int p) {
    //if  all lead to win, it loses
    if (vis[v]) return;
    int cntlose = 0;
    int a = 0, b = 0;
    for (auto& x : adj[v]) {
        if (x == p) continue;
        dfs2(x, v);
        if (win2[x]) a += cnt2[x];
        else b += cnt2[x];
        cntlose += !win2[x];
    }
    // cout << "a" << cntlose << "," << v << "," << a << "," << b << endl;
    cnt2[v] = 0;
    if (cntlose == 1) {
        cnt2[v] = b;
    }
    if (cntlose == 0) {
        cnt2[v] = a + 1;
    }
    win2[v] = cntlose ? 1 : 0;
}

void cd(int v) {
    dfs(v, -1);
    int N = sz[v];
    int p = v;
    bool cont = 1;
    while (cont) {
        cont = 0;
        for (auto& x : adj[v]) {
            if (sz[x] >= N / 2 && !vis[x] && x != p) {
                p = v; v = x;
                cont = 1;
                break;
            }
        }
    }
    cnt2[v] = 0, win2[v] = 0;
    vis[v] = 1;
    int cntlose = 0, a = 0, b = 0;
    for (auto& x : adj[v]) {
        dfs2(x, v);
        if (win2[x]) a += cnt2[x];
        else b += cnt2[x];
        cntlose += !win2[x];
    }

    for (auto& x : adj[v]) {
        if (vis[x]) continue;
        dfs2(x, v);
        if (win2[x]) a -= cnt2[x];
        else b -= cnt2[x];
        cntlose -= !win2[x];

        // cout << v << "," << cntlose << "," << a << "," << b << endl;
        cnt2[v] = 0;
        if (cntlose == 1) {
            cnt2[v] = b;
        }
        if (cntlose == 0) {
            cnt2[v] = a + 1;
        }
        win2[v] = cntlose ? 1 : 0;

        cd(x);

        dfs2(x, v);
        if (win2[x]) a += cnt2[x];
        else b += cnt2[x];
        cntlose += !win2[x];
    }
    // cout << "fin: " << v << "," << cntlose << "," << a << "," << b << endl;


    cnt[v] = 0;
    if (cntlose == 1) {
        cnt[v] = b;
    }
    if (cntlose == 0) {
        cnt[v] = a + 1;
    }

    win[v] = cntlose ? 1 : 0;
    vis[v] = 0;
}

const int mod = 1e9 + 7;

struct uwu {
    int a = 0, b = 0, c = 0, d = 0;
};

uwu combine(uwu a, uwu b) {
    uwu res;
    res.a = (a.a * b.a + a.c * b.c) % mod;
    res.b = (a.a * b.b + a.c * b.d + a.b * (b.a + b.b + b.c + b.d)) % mod;
    res.c = (a.c * b.a + a.a * b.c) % mod;
    res.d = (a.c * b.b + a.a * b.d + a.d * (b.a + b.b + b.c + b.d)) % mod;
    return res;
}

uwu binpow(uwu a, int b) {
    if (b == 1) return a;
    uwu c = binpow(combine(a, a), b / 2);
    if (b & 1) c = combine(c, a);
    return c;
}

void solve() {
    int N, D; cin >> N >> D;
    for (int i = 0; i < N - 1; i++) {
        int a, b; cin >> a >> b; a--;b--;
        adj[a].push_back(b);
        adj[b].push_back(a);
    }
    cd(0);
    int cntw = 0, cntl = 0;
    uwu x;
    for (int i = 0; i < N; i++) {
        if (win[i]) {
            cntw++;
            x.a += cnt[i];
            x.b += N - cnt[i];
        } else {
            cntl++;
            x.c += cnt[i];
            x.d += N - cnt[i];
        }
    }

    cntl %= mod; cntw %= mod; x.a %= mod; x.b %= mod; x.c %= mod; x.d %= mod;

    if (D == 0) {
        cout << win[0] << endl;
    } else if (D == 1) {
        uwu v;

        if (win[0]) {
            v.a += cnt[0];
            v.b += N - cnt[0];
        } else {
            v.c += cnt[0];
            v.d += N - cnt[0];
        }
        //     cout << v.c << "," << cntl << endl;
        cout << (v.a * cntw + v.b * N + v.c * cntl) % mod << endl;
    } else {

        uwu v;

        if (win[0]) {
            v.a += cnt[0];
            v.b += N - cnt[0];
        } else {
            v.c += cnt[0];
            v.d += N - cnt[0];
        }
        v = combine(v, binpow(x, D - 1));
        cout << (v.a * cntw + v.b * N + v.c * cntl) % mod << endl;
    }
}

int32_t main() {
    int t = 1;
    //cin >> t;
    while (t--)
        solve();
}
# 결과 실행 시간 메모리 Grader output
1 Correct 2 ms 2644 KB Output is correct
2 Correct 2 ms 2644 KB Output is correct
# 결과 실행 시간 메모리 Grader output
1 Correct 2 ms 2644 KB Output is correct
2 Correct 1 ms 2644 KB Output is correct
3 Correct 2 ms 2644 KB Output is correct
4 Correct 1 ms 2644 KB Output is correct
5 Correct 1 ms 2644 KB Output is correct
# 결과 실행 시간 메모리 Grader output
1 Correct 1 ms 2644 KB Output is correct
2 Correct 1 ms 2644 KB Output is correct
3 Correct 1 ms 2644 KB Output is correct
4 Correct 1 ms 2644 KB Output is correct
5 Correct 2 ms 2644 KB Output is correct
6 Correct 2 ms 2644 KB Output is correct
# 결과 실행 시간 메모리 Grader output
1 Correct 1 ms 2644 KB Output is correct
2 Correct 1 ms 2644 KB Output is correct
3 Correct 1 ms 2644 KB Output is correct
4 Correct 1 ms 2644 KB Output is correct
5 Correct 2 ms 2644 KB Output is correct
6 Correct 2 ms 2644 KB Output is correct
7 Correct 2 ms 2772 KB Output is correct
8 Correct 2 ms 2772 KB Output is correct
9 Correct 2 ms 2644 KB Output is correct
10 Correct 2 ms 2680 KB Output is correct
11 Correct 2 ms 2772 KB Output is correct
# 결과 실행 시간 메모리 Grader output
1 Correct 1 ms 2644 KB Output is correct
2 Correct 1 ms 2644 KB Output is correct
3 Correct 1 ms 2644 KB Output is correct
4 Correct 1 ms 2644 KB Output is correct
5 Correct 2 ms 2644 KB Output is correct
6 Correct 2 ms 2644 KB Output is correct
7 Correct 2 ms 2772 KB Output is correct
8 Correct 2 ms 2772 KB Output is correct
9 Correct 2 ms 2644 KB Output is correct
10 Correct 2 ms 2680 KB Output is correct
11 Correct 2 ms 2772 KB Output is correct
12 Correct 239 ms 15672 KB Output is correct
13 Correct 281 ms 17072 KB Output is correct
14 Correct 56 ms 11124 KB Output is correct
15 Correct 140 ms 11272 KB Output is correct
16 Correct 164 ms 11468 KB Output is correct
# 결과 실행 시간 메모리 Grader output
1 Correct 1 ms 2644 KB Output is correct
2 Correct 1 ms 2644 KB Output is correct
3 Correct 1 ms 2644 KB Output is correct
4 Correct 1 ms 2644 KB Output is correct
5 Correct 2 ms 2644 KB Output is correct
6 Correct 2 ms 2644 KB Output is correct
7 Correct 2 ms 2772 KB Output is correct
8 Correct 2 ms 2772 KB Output is correct
9 Correct 2 ms 2644 KB Output is correct
10 Correct 2 ms 2680 KB Output is correct
11 Correct 2 ms 2772 KB Output is correct
12 Correct 2 ms 2644 KB Output is correct
13 Correct 2 ms 2644 KB Output is correct
14 Correct 2 ms 2644 KB Output is correct
15 Correct 1 ms 2644 KB Output is correct
16 Correct 2 ms 2644 KB Output is correct
17 Correct 2 ms 2644 KB Output is correct
18 Correct 1 ms 2644 KB Output is correct
19 Correct 2 ms 2644 KB Output is correct
20 Correct 1 ms 2644 KB Output is correct
21 Correct 2 ms 2784 KB Output is correct
22 Correct 2 ms 2772 KB Output is correct
23 Correct 2 ms 2772 KB Output is correct
24 Correct 2 ms 2772 KB Output is correct
25 Correct 2 ms 2644 KB Output is correct
26 Correct 2 ms 2772 KB Output is correct
27 Correct 2 ms 2772 KB Output is correct
28 Correct 2 ms 2644 KB Output is correct
29 Correct 2 ms 2772 KB Output is correct
30 Correct 2 ms 2644 KB Output is correct
# 결과 실행 시간 메모리 Grader output
1 Correct 1 ms 2644 KB Output is correct
2 Correct 1 ms 2644 KB Output is correct
3 Correct 1 ms 2644 KB Output is correct
4 Correct 1 ms 2644 KB Output is correct
5 Correct 2 ms 2644 KB Output is correct
6 Correct 2 ms 2644 KB Output is correct
7 Correct 2 ms 2772 KB Output is correct
8 Correct 2 ms 2772 KB Output is correct
9 Correct 2 ms 2644 KB Output is correct
10 Correct 2 ms 2680 KB Output is correct
11 Correct 2 ms 2772 KB Output is correct
12 Correct 239 ms 15672 KB Output is correct
13 Correct 281 ms 17072 KB Output is correct
14 Correct 56 ms 11124 KB Output is correct
15 Correct 140 ms 11272 KB Output is correct
16 Correct 164 ms 11468 KB Output is correct
17 Correct 2 ms 2644 KB Output is correct
18 Correct 2 ms 2644 KB Output is correct
19 Correct 2 ms 2644 KB Output is correct
20 Correct 1 ms 2644 KB Output is correct
21 Correct 2 ms 2644 KB Output is correct
22 Correct 2 ms 2644 KB Output is correct
23 Correct 1 ms 2644 KB Output is correct
24 Correct 2 ms 2644 KB Output is correct
25 Correct 1 ms 2644 KB Output is correct
26 Correct 2 ms 2784 KB Output is correct
27 Correct 2 ms 2772 KB Output is correct
28 Correct 2 ms 2772 KB Output is correct
29 Correct 2 ms 2772 KB Output is correct
30 Correct 2 ms 2644 KB Output is correct
31 Correct 2 ms 2772 KB Output is correct
32 Correct 2 ms 2772 KB Output is correct
33 Correct 2 ms 2644 KB Output is correct
34 Correct 2 ms 2772 KB Output is correct
35 Correct 2 ms 2644 KB Output is correct
36 Correct 246 ms 15680 KB Output is correct
37 Correct 268 ms 17080 KB Output is correct
38 Correct 55 ms 11084 KB Output is correct
39 Correct 158 ms 11300 KB Output is correct
40 Correct 144 ms 11304 KB Output is correct
41 Correct 223 ms 15708 KB Output is correct
42 Correct 218 ms 15932 KB Output is correct
43 Correct 50 ms 10148 KB Output is correct
44 Correct 141 ms 11388 KB Output is correct
45 Correct 141 ms 11204 KB Output is correct
# 결과 실행 시간 메모리 Grader output
1 Correct 2 ms 2644 KB Output is correct
2 Correct 2 ms 2644 KB Output is correct
3 Correct 2 ms 2644 KB Output is correct
4 Correct 1 ms 2644 KB Output is correct
5 Correct 2 ms 2644 KB Output is correct
6 Correct 1 ms 2644 KB Output is correct
7 Correct 1 ms 2644 KB Output is correct
8 Correct 1 ms 2644 KB Output is correct
9 Correct 1 ms 2644 KB Output is correct
10 Correct 1 ms 2644 KB Output is correct
11 Correct 1 ms 2644 KB Output is correct
12 Correct 2 ms 2644 KB Output is correct
13 Correct 2 ms 2644 KB Output is correct
14 Correct 2 ms 2772 KB Output is correct
15 Correct 2 ms 2772 KB Output is correct
16 Correct 2 ms 2644 KB Output is correct
17 Correct 2 ms 2680 KB Output is correct
18 Correct 2 ms 2772 KB Output is correct
19 Correct 239 ms 15672 KB Output is correct
20 Correct 281 ms 17072 KB Output is correct
21 Correct 56 ms 11124 KB Output is correct
22 Correct 140 ms 11272 KB Output is correct
23 Correct 164 ms 11468 KB Output is correct
24 Correct 2 ms 2644 KB Output is correct
25 Correct 2 ms 2644 KB Output is correct
26 Correct 2 ms 2644 KB Output is correct
27 Correct 1 ms 2644 KB Output is correct
28 Correct 2 ms 2644 KB Output is correct
29 Correct 2 ms 2644 KB Output is correct
30 Correct 1 ms 2644 KB Output is correct
31 Correct 2 ms 2644 KB Output is correct
32 Correct 1 ms 2644 KB Output is correct
33 Correct 2 ms 2784 KB Output is correct
34 Correct 2 ms 2772 KB Output is correct
35 Correct 2 ms 2772 KB Output is correct
36 Correct 2 ms 2772 KB Output is correct
37 Correct 2 ms 2644 KB Output is correct
38 Correct 2 ms 2772 KB Output is correct
39 Correct 2 ms 2772 KB Output is correct
40 Correct 2 ms 2644 KB Output is correct
41 Correct 2 ms 2772 KB Output is correct
42 Correct 2 ms 2644 KB Output is correct
43 Correct 246 ms 15680 KB Output is correct
44 Correct 268 ms 17080 KB Output is correct
45 Correct 55 ms 11084 KB Output is correct
46 Correct 158 ms 11300 KB Output is correct
47 Correct 144 ms 11304 KB Output is correct
48 Correct 223 ms 15708 KB Output is correct
49 Correct 218 ms 15932 KB Output is correct
50 Correct 50 ms 10148 KB Output is correct
51 Correct 141 ms 11388 KB Output is correct
52 Correct 141 ms 11204 KB Output is correct
53 Correct 252 ms 17184 KB Output is correct
54 Correct 248 ms 15956 KB Output is correct
55 Correct 44 ms 9476 KB Output is correct
56 Correct 195 ms 14108 KB Output is correct
57 Correct 135 ms 11484 KB Output is correct
58 Correct 135 ms 11468 KB Output is correct
59 Correct 135 ms 11264 KB Output is correct
60 Correct 143 ms 11144 KB Output is correct