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QOJ

ID	题目	提交者	结果	用时	内存	语言	文件大小	提交时间	测评时间
#465307	#8551. DFS Order 5	ucup-team191^#	WA	26ms	9196kb	C++14	3.1kb	2024-07-06 20:00:55	2024-07-06 20:00:56

Judging History

你现在查看的是最新测评结果

[2024-07-06 20:00:56]
评测

测评结果：WA
用时：26ms
内存：9196kb

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[2024-07-06 20:00:55]
提交

answer

#include<bits/stdc++.h>

using namespace std;

typedef long long llint;
typedef pair <int, int> pi;
typedef vector <int> vi;

const int MAXN = 100005;
const int LOG = 19;

int n, q;
int par[MAXN][LOG], dub[MAXN], bio[MAXN], broj_djece[MAXN], deg[MAXN];
vector <int> v[MAXN];

void dfs (int x, int rod) {
    par[x][0] = rod;
    dub[x] = 1 + dub[rod];
    for (auto sus : v[x]) {
        if (sus == rod) continue;
        dfs(sus, x);
        broj_djece[x]++;
    }
}

void precompute_lca () {
    for (int i = 1; i < LOG; i++) {
        for (int j = 1; j <= n; j++) {
            par[j][i] = par[par[j][i - 1]][i - 1];
        }
    }
}

int kth (int x, int k) {
    int pot = 0;
    while (k > 0) {
        if (k % 2 == 1) x = par[x][pot];
        k /= 2;
        pot++;
    }
    return x;
}

int lca (int a, int b) {
    if (dub[a] < dub[b]) swap(a, b);
    a = kth(a, dub[a] - dub[b]);
    if (a == b) return a;
    for (int i = LOG - 1; i >= 0; i--) {
        if (par[a][i] != par[b][i]) {
            a = par[a][i];
            b = par[b][i];
        }
    }
    return par[a][0];
}

bool ima_duplica (const vi& r) {
    for (auto x : r) {
        bio[x] = 0;
    }
    for (auto x : r) {
        bio[x]++;
        if (bio[x] == 2) return 1;
    }
    return 0;
}

bool popaj (vector <pi> &st) {
    int node = st.back().first, tip = st.back().second;
    if (tip == 1) {
        st.pop_back();
        return 1;
    }
    if (deg[node] == broj_djece[node]) {
        st.pop_back();
        deg[par[node][0]]++;
        return 1;
    }
    return 0;
}

bool solve (const vi& r) {
    if (ima_duplica(r)) return 0;

    vector <pi> st;
    st.push_back({r[0], 0});

    for (auto x : r) {
        deg[x] = 0;
    }

    for (int i = 1; i < (int)r.size(); i++) {
        int novi = r[i];
        int stari = st.back().first;
        int L = lca(stari, novi);

        if (L == novi) {
            return 0;
        }

        if (L == stari) {
            if (par[novi][0] != stari) {
                return 0;
            }
            st.push_back({novi, 0});
        } else {
            while (!st.empty() && lca(st.back().first, novi) != st.back().first) {
                if (popaj(st) == 0) return 0;
            }
            if (st.empty() || st.back().first != L) {
                st.push_back({L, 1});
            }
            if (par[novi][0] != L) {
                return 0;
            }
            st.push_back({novi, 0});
        }
    }

    return 1;
}

int main () {
    ios_base::sync_with_stdio(false);
    cin.tie(0);
    cin >> n >> q;
    for (int i = 0; i < n - 1; i++) {
        int a, b;
        cin >> a >> b;
        v[a].push_back(b);
        v[b].push_back(a);
    }
    dfs(1, 0);
    precompute_lca();
    for (int i = 0; i < q; i++) {
        int siz;
        cin >> siz;
        vi r(siz);
        for (int j = 0; j < siz; j++) {
            cin >> r[j];
        }
        int res = solve(r);
        if (res) cout << "Yes\n"; else cout << "No\n";
    }
    return 0;
}

源文件, 语言: C++14

詳細信息

Test #1:

score: 100

Accepted

time: 2ms

memory: 9196kb

input:

6 7
1 2
1 3
2 4
3 5
2 6
2 4 1
2 4 2
2 4 3
2 4 4
2 4 5
2 4 6
6 1 2 6 4 3 5

output:

No
No
Yes
No
No
Yes
Yes

result:

ok 7 tokens

Test #2:

score: -100

Wrong Answer

time: 26ms

memory: 8228kb

input:

10 100000
7 2
1 7
7 10
8 6
8 7
1 3
4 5
9 5
5 8
8 8 9 7 2 8 1 6 1
4 8 3 5 2
6 7 10 3 9 9 1
1 1
8 10 3 2 9 3 8 7 3
7 5 6 2 8 5 9 1
6 3 4 6 2 1 3
5 8 9 2 4 9
1 3
2 1 5
5 8 5 1 7 9
10 5 2 9 2 6 4 10 6 3 8
3 4 5 8
2 8 4
9 4 10 1 2 4 3 3 6 3
1 3
6 1 1 6 8 3 1
3 7 3 2
3 9 1 5
4 3 7 8 10
9 4 2 3 10 2 5 4 3 ...

output:

No
No
No
Yes
No
No
No
No
Yes
No
No
No
No
No
No
Yes
No
No
No
No
No
No
No
No
No
No
No
No
No
No
No
Yes
No
No
No
No
No
No
Yes
No
No
No
No
No
Yes
Yes
No
No
No
No
No
No
No
No
No
No
No
No
No
No
No
No
No
No
No
No
No
No
No
No
Yes
No
No
Yes
Yes
No
No
No
No
Yes
No
No
No
No
No
No
No
No
Yes
No
No
No
No
No
No
No
...

result:

wrong answer 89th words differ - expected: 'No', found: 'Yes'