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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
#415408#852. JellyfishMobed#WA 93ms6144kbC++142.3kb2024-05-20 21:03:332024-05-20 21:03:34

Judging History

This is the latest submission verdict.

  • [2024-05-20 21:03:34]
  • Judged
  • Verdict: WA
  • Time: 93ms
  • Memory: 6144kb
  • [2024-05-20 21:03:33]
  • Submitted

answer

#include<bits/stdc++.h>

using namespace std;
const int inf = 1e9 + 1;
const int MOD = 1e9 + 7;

/*
const int N = 1e5 + 5;
int fac[N], inv[N];

int sum(int a, int b) { return (a + b + MOD + MOD) % MOD; }
int mul(int a, int b) { return 1ll * a * b % MOD; }
int Pow(int a, int b) {
    int res = 1;
    for (; b; b>>=1, a = mul(a, a)) if (b&1) {
        res = mul(res, a);
    }
    return res;
}
int C(int n, int k) {
    return mul(fac[n], mul(inv[k], inv[n - k]));
}
void prep() {
    fac[0] = 1;
    for (int i = 1; i < N; i++) fac[i] = mul(fac[i - 1], i);
    inv[N - 1] = Pow(fac[N - 1], MOD - 2);
    for (int i = N - 2; i >= 0; i--) inv[i] = mul(inv[i + 1], i + 1);
}
*/

const int N = 1e5 + 5;
vector<int> g[N];
vector<int> circle;
int mark[N];
int lf[N];

int dfs(int v, int p = 0) {
    mark[v] = 1;
    int ch = 0;
    for (int u : g[v]) if (u != p) {
        if (!mark[u]) {
            ch = max(ch, dfs(u, v));
        } else if (mark[u] == 1) {
            ch = 2;
            circle.push_back(u);
        }
    }
    if (!circle.empty() && v == circle[0]) 
        return 1;
    mark[v] = ch;
    if (mark[v] == 2) {
        circle.push_back(v);
    }
    return mark[v];
}

int count_leaf(int v, int r) {
    mark[v] = 2;
    int leaf = 0;
    for (int u : g[v]) if (mark[u] != 2) {
        leaf += count_leaf(u, r);
    }
    if (leaf == 0 && v != r)
        return 1;
    else
        return leaf;
}
void Solve() {
    int n; cin >> n;
    for (int i = 1; i <= n; i++) g[i].clear(), lf[i] = 0, mark[i] = 0;
    for (int i = 1; i <= n; i++) {
        int u, v; cin >> u >> v;
        g[u].push_back(v);
        g[v].push_back(u);
    }
    circle.clear();
    dfs(1);
    int sum = 0;
    for (int v : circle) {
        lf[v] = count_leaf(v, v);
        sum += lf[v];
        // cout << v << " " << lf[v] << "\n";
    }
    int ans = 3;
    for (int i = 0; i < circle.size(); i++) {
        int v = circle[i];
        int u = circle[(i + 1) % circle.size()];
        ans = max(ans, sum - lf[u] - lf[v] + 2);
    }
    cout << ans << "\n";
}

int main() {
    // prep();
    // cout << C(5, 4) << endl;
    ios::sync_with_stdio(0), cin.tie(0), cout.tie(0);
    int t = 1; cin >> t;
    while (t--) {
        Solve();
    }
}

详细

Test #1:

score: 100
Accepted
time: 2ms
memory: 6072kb

input:

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

output:

4
3

result:

ok 2 number(s): "4 3"

Test #2:

score: -100
Wrong Answer
time: 93ms
memory: 6144kb

input:

85665
6
3 2
4 1
4 6
2 1
2 6
5 1
7
6 2
6 3
5 1
1 2
2 4
4 7
3 7
7
6 1
6 7
1 4
1 3
7 5
5 3
4 2
7
6 2
7 4
7 5
3 1
3 4
2 5
1 4
7
7 2
2 6
5 4
5 6
5 1
3 1
4 6
7
3 5
3 1
3 7
3 2
5 1
5 4
4 6
7
4 5
4 1
3 6
3 7
6 7
6 1
2 1
7
5 3
7 3
1 4
6 2
6 3
2 3
4 3
7
2 3
2 6
2 4
7 5
3 5
5 1
1 4
7
3 4
3 7
5 6
2 7
4 6
6 7
6 ...

output:

4
3
3
3
3
4
4
5
4
5
4
4
3
4
4
3
4
4
4
4
4
5
3
4
3
4
3
9
4
4
3
4
8
3
97
5
4
3
5
4
4
4
4
3
4
4
4
4
5
3
5
4
3
4
94
4
4
4
5
4
3
4
3
5
4
3
4
3
3
4
4
4
4
4
3
4
4
4
3
3
3
4
4
3
4
4
4
4
4
4
3
3
5
5
4
5
4
3
4
4
3
3
3
5
4
4
4
6
4
5
5
5
4
3
5
4
4
3
4
10
4
3
3
4
4
3
4
4
4
3
5
3
4
4
3
3
3
4
5
95
5
104
4
4
4
3
4
...

result:

wrong answer 35th numbers differ - expected: '98', found: '97'