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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
#624313#7895. Graph Partitioning 2afyTL 425ms287200kbC++203.5kb2024-10-09 15:31:112024-10-09 15:31:11

Judging History

你现在查看的是最新测评结果

  • [2024-10-09 15:31:11]
  • 评测
  • 测评结果:TL
  • 用时:425ms
  • 内存:287200kb
  • [2024-10-09 15:31:11]
  • 提交

answer

#include <bits/stdc++.h>
#ifdef LOCAL
#include "debug.h"
#else
#define deb(...)
#endif
using namespace std;
#define ll long long
// #define int long long
#define ull unsigned long long
#define pii pair<int, int>
#define db double
#define baoliu(x, y) cout << fixed << setprecision(y) << x
#define endl "\n"
#define alls(x) (x).begin(), (x).end()
#define fs first
#define sec second
#define bug(x) cerr << #x << " = " << x << endl
const int N = 3e5 + 10;
const int M = 1e6 + 10;
const int inf = 0x3f3f3f3f;
const int p = 998244353;
const double eps = 1e-8;
const double PI = acos(-1.0);
int T;
int n, K;
int f[N][666], siz[N], g[666];
unordered_map<int, int> F[N], G;
vector<int> e[N];
void chushihua() {
    for (int i = 1; i <= n; i++) e[i].clear();
    int sq = 660;
    if (K <= sq)
        for (int i = 1; i <= n; i++)
            for (int j = 0; j <= K + 1; j++) f[i][j] = 0;
    else
        F[1].clear();
}

void DFS1(int u, int fa) {
    // 当k<=sq时,直接记录包含当前子树根节点的连通块大小进行树上背包DP即可
    siz[u] = 1;
    f[u][1] = 1;
    for (auto v : e[u]) {
        if (v == fa)
            continue;
        DFS1(v, u);
        for (int j = 0; j <= K + 1; j++) g[j] = 0;  // 由于这个背包是必须强制选,所以之前的状态需要删除,我用临时数组g来实现转移。
        for (int j = 0; j <= min(K, siz[v]); j++) {
            for (int k = min(K + 1 - j, siz[u]); k >= 1; k--)
                (g[j + k] += (ll)((ll)f[v][j] * (ll)f[u][k]) % p) %= p;
        }
        for (int j = 0; j <= K + 1; j++) f[u][j] = g[j];
        siz[u] += siz[v];
    }
    f[u][0] = (f[u][K] + f[u][K + 1]) % p;
}

void DFS2(int u, int fa) {
    siz[u] = 1;
    F[u][1] = 1;  // k 比较大时
//使用 unordered_map 记录答案不为 0 的值进行树上背包
    for (auto v : e[u]) {
        if (v == fa)
            continue;
        DFS2(v, u);
        G.clear();
        for (auto j : F[v]) {
            for (auto k : F[u]) {
                if (j.first + k.first > K + 1)
                    continue;
                (G[j.first + k.first] += (ll)((ll)j.second * (ll)k.second) % p) %= p;
            }
        }
        F[u].clear();
        for (auto j : G) F[u][j.first] = j.second;
        siz[u] += siz[v];
    }
    F[u][0] = (F[u][K] + F[u][K + 1]) % p;
    // if (F[u][K] == 0)
    //     F[u].erase(K);
    // if (F[u][K + 1] == 0)
    //     F[u].erase(K + 1);  // 这三个点没有赋值,但是访问了,需要判断下是否是空键值对。
    // if (F[u][0] == 0)
    //     F[u].erase(0);
    for (int v : e[u])
        if (v != fa)
            F[v].clear();
}

void solve() {
    int x, y;
    chushihua();
    cin >> n >> K;
    deb(n, K);
    int sq = 660;
    for (int i = 1; i < n; i++) {
        cin >> x >> y;
        e[x].push_back(y);
        e[y].push_back(x);
    }
    if (K <= sq) {
        DFS1(1, 1);
        cout << (f[1][0] % p + p) % p << endl;
    } else {
        DFS2(1, 1);
        cout << (F[1][0] % p + p) % p << endl;
    }
}

signed main() {
    cin.tie(0);
    ios::sync_with_stdio(false);
#ifdef LOCAL
    double starttime = clock();
    // freopen("in.txt", "r", stdin);
    // freopen("out.txt", "w", stdout);
#endif
    int t = 1;
    cin >> t;
    deb(t);
    while (t--) solve();
#ifdef LOCAL
    double endtime = clock();
    cerr << "Time Used: " << (double)(endtime - starttime) / CLOCKS_PER_SEC * 1000 << " ms" << endl;
#endif
    return 0;
}

详细

Test #1:

score: 100
Accepted
time: 0ms
memory: 20912kb

input:

2
8 2
1 2
3 1
4 6
3 5
2 4
8 5
5 7
4 3
1 2
1 3
2 4

output:

2
1

result:

ok 2 lines

Test #2:

score: 0
Accepted
time: 128ms
memory: 29796kb

input:

5550
13 4
10 3
9 1
10 8
3 11
8 5
10 7
9 6
13 5
9 7
2 7
5 12
4 8
8 2
4 1
3 4
7 8
2 5
6 7
4 8
2 3
11 1
11 10
1 4
9 10
8 4
3 6
5 7
6 1
10 2
11 7
11 1
17 2
14 16
13 15
17 3
15 11
1 6
13 2
13 17
4 8
14 10
8 14
14 5
9 12
14 2
12 17
17 6
15 7
14 6
2 14
2 13
2 4
8 4
3 11
7 3
14 1
11 9
13 3
5 10
6 8
3 10
14 ...

output:

0
3
112
0
1
0
1
0
0
0
1
0
1
0
0
1
0
140
0
0
0
814
1
6
1
1
2
2
0
612
0
1
0
0
0
1
1
0
0
121
4536
0
0
1718
0
0
1
0
444
1
1908
1813
3
74
0
1
0
46
0
0
0
0
0
0
0
0
0
1
0
1
1
1
239
0
0
0
1
0
0
0
1
0
1
0
0
1
1
0
0
0
1
0
0
0
48
0
2
0
0
0
1
364
0
206
0
0
76
0
1
0
0
2
0
1
2
0
0
1
0
0
4
0
1
1
0
0
1
1
1
0
0
1
1
...

result:

ok 5550 lines

Test #3:

score: 0
Accepted
time: 250ms
memory: 286864kb

input:

3
99990 259
23374 69108
82204 51691
8142 67119
48537 97966
51333 44408
33147 68485
21698 86824
15746 58746
78761 86975
58449 61819
69001 68714
25787 2257
25378 14067
64899 68906
29853 31359
75920 85420
76072 11728
63836 55505
43671 98920
77281 25176
40936 66517
61029 61440
66908 52300
92101 59742
69...

output:

259200
247
207766300

result:

ok 3 lines

Test #4:

score: 0
Accepted
time: 425ms
memory: 287200kb

input:

3
99822 332
11587 83046
63424 60675
63423 73718
74622 40130
5110 26562
28361 80899
30886 70318
8708 11068
34855 96504
7904 75735
31904 42745
87892 55105
82374 81319
77407 82147
91475 12343
13470 95329
58766 95716
83232 44156
75907 92437
69785 93598
47857 33018
62668 31394
24238 72675
98254 43583
180...

output:

315881300
4505040
185631154

result:

ok 3 lines

Test #5:

score: -100
Time Limit Exceeded

input:

3
99021 1000
41739 4318
72541 76341
31227 15416
49232 13808
50837 51259
74464 11157
92684 84646
95226 64673
74155 82511
33301 31373
5901 29318
38227 98893
96752 57411
35167 42401
24344 90803
6956 33753
51120 24535
29594 2646
70305 32961
93079 38070
49273 48987
62799 77986
94353 84447
74970 31546
263...

output:


result: