답안 #934776

# 제출 시각 아이디 문제 언어 결과 실행 시간 메모리
934776 2024-02-28T01:08:36 Z eysbutno Hard route (IZhO17_road) C++17
100 / 100
613 ms 132180 KB
#include <bits/stdc++.h>
using namespace std;
using ll = long long;
using pii = pair<int, int>;
#define all(x) begin(x), end(x)
#define sz(x) (int) (x).size()
#define f first 
#define s second 

template<class T> bool smin(T& a, T b) {
    return b < a ? a = b, 1 : 0;
}
template<class T> bool smax(T& a, T b) {
    return b > a ? a = b, 1 : 0;
}
int main() {
    cin.tie(0) -> sync_with_stdio(0);
    int n; cin >> n;
    vector adj(n, vector<int>());
    for (int i = 1; i < n; i++) {
        int x, y; cin >> x >> y;
        adj[--x].push_back(--y);
        adj[y].push_back(x);
    }
    vector<int> d(n), c(n);
    auto dfs = [&](int u, int p, auto&& dfs) -> void {
        d[u] = 0, c[u] = 1;
        for (int v : adj[u]) if (v != p) {
            dfs(v, u, dfs);
            if (smax(d[u], d[v] + 1)) {
                c[u] = c[v];
            } else if (d[v] + 1 == d[u]) {
                c[u] += c[v];
            }
        }
    }; dfs(0, -1, dfs);
    ll hard = 0, cnt = 1;
    auto dfs2 = [&](int u, int p, int pd, int pc, 
                    auto&& dfs2) -> void {
        vector<pair<ll, ll>> opt;
        if (u > 0 || sz(adj[u]) == 1) {
            opt.push_back({pd, pc});
        }
        for (int v : adj[u]) if (v != p) {
            opt.push_back({d[v] + 1, c[v]});
        }
        sort(all(opt), greater<>());
        if (sz(adj[u]) >= 3) { // can form nonzero path
            ll cur = opt[0].f * (opt[1].f + opt[2].f), 
               num = 0, ties = 0;
            for (auto [k, v] : opt) {
                if (k == opt[2].f) ties += v;
            }
            // case 1: all are distinct
            if (opt[0].f != opt[1].f &&
                opt[1].f != opt[2].f) {
                num = opt[1].s * ties;
            }
            // case 2: all are the same
            else if (opt[0].f == opt[1].f &&
                opt[1].f == opt[2].f) {
                num = ties * ties;
				for (auto [k, v] : opt) {
					if (k == opt[2].f) num -= v * v;
				}
				num /= 2;
            }
            // case 3: first two are the same
            else if (opt[0].f == opt[1].f) {
                num = (opt[0].s + opt[1].s) * ties;
            }
            // case 4: last two are the same
            else {
               	num = ties * ties;
				for (auto [k, v] : opt) {
					if (k == opt[2].f) num -= v * v;
				}
				num /= 2;
            }
            if (smax(hard, cur)) {
                cnt = num;
            } else if (hard == cur) {
                cnt += num;
            }
        }
        // processing parent dist & parent count
        ll l1 = 0, l2 = 0, cnt1 = 0, cnt2 = 0;
        for (auto [k, v] : opt) {
            // all paths will increase by len 1
            if (k + 1 > l1) {
                swap(l1, l2), swap(cnt1, cnt2);
                l1 = k + 1, cnt1 = v;
            } else if (k + 1 == l1) {
                cnt1 += v;
            } else if (k + 1 > l2) {
                l2 = k + 1, cnt2 = v;
            } else if (k + 1 == l2) {
                cnt2 += v;
            }
        }
        for (int v : adj[u]) if (v != p) {
            if (d[v] + 2 == l1) {
                (c[v] == cnt1) ? dfs2(v, u, l2, cnt2, dfs2) :
                            	 dfs2(v, u, l1, cnt1 - c[v], dfs2);
            } else {
                dfs2(v, u, l1, cnt1, dfs2);
            }
        }
    }; dfs2(0, -1, 0, 1, dfs2);
    cout << hard << ' ' << cnt << '\n';
}
# 결과 실행 시간 메모리 Grader output
1 Correct 0 ms 348 KB Output is correct
2 Correct 0 ms 348 KB Output is correct
3 Correct 0 ms 348 KB Output is correct
4 Correct 0 ms 348 KB Output is correct
5 Correct 0 ms 348 KB Output is correct
6 Correct 0 ms 348 KB Output is correct
7 Correct 0 ms 348 KB Output is correct
8 Correct 0 ms 348 KB Output is correct
9 Correct 0 ms 348 KB Output is correct
10 Correct 1 ms 344 KB Output is correct
11 Correct 0 ms 348 KB Output is correct
12 Correct 0 ms 348 KB Output is correct
13 Correct 0 ms 348 KB Output is correct
14 Correct 0 ms 348 KB Output is correct
15 Correct 0 ms 348 KB Output is correct
16 Correct 1 ms 348 KB Output is correct
17 Correct 0 ms 348 KB Output is correct
18 Correct 0 ms 348 KB Output is correct
19 Correct 0 ms 348 KB Output is correct
20 Correct 0 ms 344 KB Output is correct
21 Correct 0 ms 348 KB Output is correct
22 Correct 0 ms 348 KB Output is correct
23 Correct 0 ms 348 KB Output is correct
24 Correct 1 ms 348 KB Output is correct
# 결과 실행 시간 메모리 Grader output
1 Correct 0 ms 348 KB Output is correct
2 Correct 0 ms 348 KB Output is correct
3 Correct 0 ms 348 KB Output is correct
4 Correct 0 ms 348 KB Output is correct
5 Correct 0 ms 348 KB Output is correct
6 Correct 0 ms 348 KB Output is correct
7 Correct 0 ms 348 KB Output is correct
8 Correct 0 ms 348 KB Output is correct
9 Correct 0 ms 348 KB Output is correct
10 Correct 1 ms 344 KB Output is correct
11 Correct 0 ms 348 KB Output is correct
12 Correct 0 ms 348 KB Output is correct
13 Correct 0 ms 348 KB Output is correct
14 Correct 0 ms 348 KB Output is correct
15 Correct 0 ms 348 KB Output is correct
16 Correct 1 ms 348 KB Output is correct
17 Correct 0 ms 348 KB Output is correct
18 Correct 0 ms 348 KB Output is correct
19 Correct 0 ms 348 KB Output is correct
20 Correct 0 ms 344 KB Output is correct
21 Correct 0 ms 348 KB Output is correct
22 Correct 0 ms 348 KB Output is correct
23 Correct 0 ms 348 KB Output is correct
24 Correct 1 ms 348 KB Output is correct
25 Correct 3 ms 1112 KB Output is correct
26 Correct 3 ms 1116 KB Output is correct
27 Correct 2 ms 1116 KB Output is correct
28 Correct 2 ms 1116 KB Output is correct
29 Correct 2 ms 1116 KB Output is correct
30 Correct 2 ms 1116 KB Output is correct
31 Correct 2 ms 1116 KB Output is correct
32 Correct 2 ms 1112 KB Output is correct
33 Correct 2 ms 1116 KB Output is correct
34 Correct 2 ms 1116 KB Output is correct
35 Correct 2 ms 1116 KB Output is correct
36 Correct 2 ms 1116 KB Output is correct
37 Correct 2 ms 1116 KB Output is correct
38 Correct 2 ms 1628 KB Output is correct
39 Correct 2 ms 860 KB Output is correct
40 Correct 2 ms 860 KB Output is correct
41 Correct 2 ms 604 KB Output is correct
42 Correct 2 ms 604 KB Output is correct
43 Correct 2 ms 604 KB Output is correct
44 Correct 2 ms 604 KB Output is correct
45 Correct 2 ms 604 KB Output is correct
46 Correct 2 ms 604 KB Output is correct
47 Correct 2 ms 860 KB Output is correct
48 Correct 2 ms 860 KB Output is correct
# 결과 실행 시간 메모리 Grader output
1 Correct 0 ms 348 KB Output is correct
2 Correct 0 ms 348 KB Output is correct
3 Correct 0 ms 348 KB Output is correct
4 Correct 0 ms 348 KB Output is correct
5 Correct 0 ms 348 KB Output is correct
6 Correct 0 ms 348 KB Output is correct
7 Correct 0 ms 348 KB Output is correct
8 Correct 0 ms 348 KB Output is correct
9 Correct 0 ms 348 KB Output is correct
10 Correct 1 ms 344 KB Output is correct
11 Correct 0 ms 348 KB Output is correct
12 Correct 0 ms 348 KB Output is correct
13 Correct 0 ms 348 KB Output is correct
14 Correct 0 ms 348 KB Output is correct
15 Correct 0 ms 348 KB Output is correct
16 Correct 1 ms 348 KB Output is correct
17 Correct 0 ms 348 KB Output is correct
18 Correct 0 ms 348 KB Output is correct
19 Correct 0 ms 348 KB Output is correct
20 Correct 0 ms 344 KB Output is correct
21 Correct 0 ms 348 KB Output is correct
22 Correct 0 ms 348 KB Output is correct
23 Correct 0 ms 348 KB Output is correct
24 Correct 1 ms 348 KB Output is correct
25 Correct 3 ms 1112 KB Output is correct
26 Correct 3 ms 1116 KB Output is correct
27 Correct 2 ms 1116 KB Output is correct
28 Correct 2 ms 1116 KB Output is correct
29 Correct 2 ms 1116 KB Output is correct
30 Correct 2 ms 1116 KB Output is correct
31 Correct 2 ms 1116 KB Output is correct
32 Correct 2 ms 1112 KB Output is correct
33 Correct 2 ms 1116 KB Output is correct
34 Correct 2 ms 1116 KB Output is correct
35 Correct 2 ms 1116 KB Output is correct
36 Correct 2 ms 1116 KB Output is correct
37 Correct 2 ms 1116 KB Output is correct
38 Correct 2 ms 1628 KB Output is correct
39 Correct 2 ms 860 KB Output is correct
40 Correct 2 ms 860 KB Output is correct
41 Correct 2 ms 604 KB Output is correct
42 Correct 2 ms 604 KB Output is correct
43 Correct 2 ms 604 KB Output is correct
44 Correct 2 ms 604 KB Output is correct
45 Correct 2 ms 604 KB Output is correct
46 Correct 2 ms 604 KB Output is correct
47 Correct 2 ms 860 KB Output is correct
48 Correct 2 ms 860 KB Output is correct
49 Correct 387 ms 67052 KB Output is correct
50 Correct 386 ms 73296 KB Output is correct
51 Correct 366 ms 78928 KB Output is correct
52 Correct 376 ms 58960 KB Output is correct
53 Correct 352 ms 76148 KB Output is correct
54 Correct 298 ms 90464 KB Output is correct
55 Correct 387 ms 72988 KB Output is correct
56 Correct 309 ms 80464 KB Output is correct
57 Correct 414 ms 89992 KB Output is correct
58 Correct 331 ms 82580 KB Output is correct
59 Correct 347 ms 82588 KB Output is correct
60 Correct 303 ms 79004 KB Output is correct
61 Correct 579 ms 132180 KB Output is correct
62 Correct 590 ms 115188 KB Output is correct
63 Correct 613 ms 66048 KB Output is correct
64 Correct 563 ms 53844 KB Output is correct
65 Correct 566 ms 46388 KB Output is correct
66 Correct 507 ms 42580 KB Output is correct
67 Correct 495 ms 40272 KB Output is correct
68 Correct 570 ms 39468 KB Output is correct
69 Correct 570 ms 39248 KB Output is correct
70 Correct 519 ms 38848 KB Output is correct
71 Correct 491 ms 38812 KB Output is correct
72 Correct 480 ms 39152 KB Output is correct
73 Correct 469 ms 39252 KB Output is correct
74 Correct 519 ms 39620 KB Output is correct
75 Correct 520 ms 40136 KB Output is correct
76 Correct 431 ms 41288 KB Output is correct
77 Correct 423 ms 44008 KB Output is correct
78 Correct 244 ms 50640 KB Output is correct