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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
#662891#7860. Graph of Maximum Degree 3NCl3WA 1ms4256kbC++203.5kb2024-10-21 11:48:032024-10-21 11:48:04

Judging History

你现在查看的是最新测评结果

  • [2024-10-21 11:48:04]
  • 评测
  • 测评结果:WA
  • 用时:1ms
  • 内存:4256kb
  • [2024-10-21 11:48:03]
  • 提交

answer

#include <bits/stdc++.h>
using ll = long long;
using ld = long double;
using ull = unsigned long long;
constexpr int N = 1e5 + 10;
constexpr int inf = 1e9 + 10;
constexpr ll llinf = 1e18 + 10;
constexpr int mod = 998244353;
void debug() {
    std::cerr << "\n";
}
template<typename T, typename... Args>
void debug(T val, const Args&... args) {
    std::cerr << val << " ";
    debug(args...);
}
template<typename T>
void debug(const std::vector<T>& vec) {
    for (const T& x : vec) std::cerr << x << ' ';std::cerr << "\n";
}
struct DSU
{
    std::vector<int> f, siz, d;

    DSU() {}
    DSU(int n)
    {
        build(n);
    }

    void build(int n)
    {
        f.resize(n + 1); d.resize(n + 1);
        std::iota(f.begin(), f.end(), 0);
        siz.assign(n + 1, 1);
    }

    int find(int x)
    {
        if (x != f[x]) {
            int px = find(f[x]);
            d[x] += d[f[x]];
            f[x] = px;
        }
        return f[x];
    }

    bool same(int x, int y)
    {
        return find(x) == find(y);
    }

    bool merge(int x, int y, int op = 1)
    {
        int px = find(x), py = find(y);
        if (px == py)
        {
            return false;
        }
        siz[py] += siz[px];
        f[px] = py;
        d[px] = d[y] - d[x] + op;//要确保d[px]>0
        return true;
    }

    int size(int x)
    {
        return siz[find(x)];
    }
    int dist(int x)
    {
        return d[x];
    }
};
int pw[N];
void ncl3() {
    pw[0] = 1;
    for (int i = 1; i < N; i++) {
        pw[i] = (2ll * pw[i - 1]) % mod;
    }
    int n, m;
    std::cin >> n >> m;
    std::vector<std::vector<int>> er(n), eb(n);
    std::vector<std::array<int, 3>> edges(m);
    std::vector<int> dr(n), db(n);
    DSU S(n), dsu(n);
    for (auto& [u, v, c] : edges) {
        std::cin >> u >> v >> c;
        u--, v--;
        if (c == 0) {
            er[u].push_back(v);
            er[v].push_back(u);
            dr[u]++, dr[v]++;
        }
        else {
            eb[u].push_back(v);
            eb[v].push_back(u);
            db[u]++, db[v]++;
        }
        if (c == 0)
            S.merge(u, v);
    }
    for (auto [u, v, c] : edges) {
        if (c == 1 && S.same(u, v)) {
            dsu.merge(u, v);
        }
    }
    std::vector<int> cnt(n);
    for (int u = 0; u < n; u++) {
        if (dr[u] + db[u] == 2) {
            bool ok = 1;
            for (auto v : er[u]) {
                if (dsu.same(u, v)) {
                    if (dr[v] == 1) ok = 0;
                }
            }
            for (auto v : eb[u]) {
                if (dsu.same(u, v)) {
                    if (db[v] == 1) ok = 0;
                }
            }
            if (ok) cnt[dsu.find(u)]++;
        }
    }
    ll ans = n;
    for (int i = 0; i < n; i++) {
        if (dsu.find(i) == i) {
            ans += pw[cnt[i]];
            // debug(i, cnt[i], dsu.size(i));
            // if (dsu.size(i) != 1) {
            // }
        }
    }
    std::cout << ans % mod << "\n";
}
/*
    预处理、找性质缩小范围、集合思想、正难则反、穷举
*/
int main() {
#ifdef LOCAL
    clock_t time = clock();
    freopen("in.txt", "r", stdin);
    freopen("out.txt", "w", stdout);
#endif
    std::ios::sync_with_stdio(false);
    std::cin.tie(nullptr);
    int t = 1;
    // std::cin >> t;
    while (t--) {
        ncl3();
    }
#ifdef LOCAL
    std::cout << "Time Used:" << clock() - time << "ms" << "\n";
#endif
    return 0;
}

详细

Test #1:

score: 100
Accepted
time: 1ms
memory: 4032kb

input:

3 4
1 2 0
1 3 1
2 3 0
2 3 1

output:

5

result:

ok 1 number(s): "5"

Test #2:

score: 0
Accepted
time: 1ms
memory: 4036kb

input:

4 6
1 2 0
2 3 0
3 4 0
1 4 1
2 4 1
1 3 1

output:

5

result:

ok 1 number(s): "5"

Test #3:

score: 0
Accepted
time: 1ms
memory: 4036kb

input:

20 28
9 6 1
9 6 0
3 8 0
8 4 0
3 8 1
3 4 1
2 13 0
13 1 0
19 1 0
2 1 1
2 19 1
13 19 1
14 15 1
14 15 0
7 12 0
12 17 0
20 17 0
7 17 1
7 20 1
12 20 1
16 18 0
18 10 0
5 10 0
16 10 1
16 5 1
18 5 1
4 6 0
9 11 0

output:

27

result:

ok 1 number(s): "27"

Test #4:

score: -100
Wrong Answer
time: 1ms
memory: 4256kb

input:

100 150
93 23 0
23 81 0
76 81 0
93 81 1
93 76 1
23 76 1
100 65 0
65 56 0
19 56 0
100 56 1
100 19 1
65 19 1
2 98 0
2 98 1
26 63 0
63 90 0
26 63 1
26 90 1
6 11 0
11 67 0
6 11 1
6 67 1
37 89 0
89 64 0
25 64 0
37 64 1
37 25 1
89 25 1
84 10 0
10 29 0
75 29 0
84 29 1
84 75 1
10 75 1
7 70 1
7 70 0
28 92 0
...

output:

133

result:

wrong answer 1st numbers differ - expected: '141', found: '133'