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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
#412391#6101. Ring RoadsuomynonARE 0ms18096kbC++203.7kb2024-05-16 13:03:132024-05-16 13:03:13

Judging History

你现在查看的是最新测评结果

  • [2024-05-16 13:03:13]
  • 评测
  • 测评结果:RE
  • 用时:0ms
  • 内存:18096kb
  • [2024-05-16 13:03:13]
  • 提交

answer

#include <bits/stdc++.h>
using i64 = long long;
const int N = 2e5;
const i64 Inf = 1e18;
int n;
struct Edge { int x, y; i64 z; }ed[N + 5];
int tot;
namespace Init {

int n;
std::vector<std::pair<int, i64>> v[N + 5];
void dfs(int x) {
    for (int i = 0, pre = x; i < (int)v[x].size(); ++i) if (v[x][i].first > x) {
        ++::n;
        ed[++tot] = {pre, ::n, 0}, ed[++tot] = {::n, v[x][i].first, v[x][i].second};
        pre = ::n;
    }
    for (auto [i, c] : v[x]) if (i > x) dfs(i);
}
void solve() {
    std::cin >> n;
    for (int i = 2, x; i <= n; ++i) {
        i64 y;
        std::cin >> x >> y;
        v[x].push_back({i, y}), v[i].push_back({x, y});
    }
    ::n = n, dfs(1);
}

}
std::vector<std::array<int, 2>> tr[N + 5], gr[N + 5];
int q;
i64 ans[N + 5];
int siz[N + 5], rt, mxs;
bool vis[N + 5];
void getrt(int x, int fa, int tot) {
    siz[x] = 1;
    for (auto [i, c] : tr[x]) if (!vis[c] and c != fa) getrt(i, c, tot), siz[x] += siz[i];
    if (std::max(siz[x], tot - siz[x]) < mxs) rt = fa, mxs = std::max(siz[x], tot - siz[x]);
}
std::vector<int> nd;
namespace Dijkstra {

std::priority_queue<std::pair<i64, int>> hp;
void solve(int s, i64 *dis) {
    for (auto i : nd) dis[i] = Inf;
    dis[s] = 0, hp.push({0, s});
    while (hp.size()) {
        auto [d, p] = hp.top();
        d = -d, hp.pop();
        if (d > dis[p]) continue;
        for (auto [i, c] : gr[p]) if (d + ed[c].z < dis[i])
            dis[i] = d + ed[c].z, hp.push({-dis[i], i});
    }
}

}
int col[N + 5];
void add(int x, int fa, int v) {
    nd.push_back(x), col[x] = v;
    for (auto [i, c] : tr[x]) if (!vis[c] and c != fa) add(i, c, v);
}
i64 dis[6][N + 5];
void solve(int p, std::vector<std::array<int, 3>> qry) {
    add(ed[p].x, p, 1), add(ed[p].y, p, 2);
    std::vector<int> br;
    for (auto i : nd) for (auto [j, c] : gr[i])
        if (col[i] == 1 and col[j] == 2) br.push_back(i), br.push_back(j);
    for (int i = 0; i < (int)br.size(); ++i) Dijkstra::solve(br[i], dis[i]);
    for (auto [x, y, c] : qry)
        for (int i = 0; i < (int)br.size(); ++i)
            for (int j = 0; j < (int)br.size(); ++j)
                ans[c] = std::min(ans[c], dis[i][x] + dis[i][br[j]] + dis[j][y]);
    std::vector<std::array<int, 3>> qr[2];
    for (auto [x, y, c] : qry) if (col[x] == col[y]) qr[col[x] & 1].push_back({x, y, c});
    for (auto i : nd) {
        col[i] = 0;
        for (int j = 0; j < (int)br.size(); ++j) dis[j][i] = 0;
    }
    nd.clear(), vis[p] = 1;
    getrt(ed[p].x, 0, n);
    if (qr[1].size()) rt = 0, mxs = n, getrt(ed[p].x, 0, siz[ed[p].x]), solve(rt, qr[1]);
    if (qr[0].size()) rt = 0, mxs = n, getrt(ed[p].y, 0, siz[ed[p].y]), solve(rt, qr[0]);
}
int main() {
    std::ios::sync_with_stdio(false), std::cin.tie(0), std::cout.tie(0);
    Init::solve();
    for (int i = 1; i < n; ++i) {
        tr[ed[i].x].push_back({ed[i].y, i});
        gr[ed[i].x].push_back({ed[i].y, i});
        gr[ed[i].y].push_back({ed[i].x, i});
        tr[ed[i].y].push_back({ed[i].x, i});
    }
    int pre = 0;
    i64 x = 0;
    for (int i = 2; i <= n; ++i) if ((int)tr[i].size() == 1) {
        if (pre) ed[++tot] = {pre, i, x}, gr[pre].push_back({i, tot}), gr[i].push_back({pre, tot});
        std::cin >> x, pre = i;
    }
    for (int i = 2; i <= n; ++i) if ((int)tr[i].size() == 1) {
        ed[++tot] = {pre, i, x}, gr[pre].push_back({i, tot}), gr[i].push_back({pre, tot});
        break;
    }
    std::cin >> q;
    std::vector<std::array<int, 3>> qry;
    for (int i = 1, x, y; i <= q; ++i) std::cin >> x >> y, qry.push_back({x, y, i}), ans[i] = Inf;
    rt = 0, mxs = n, getrt(1, 0, n), solve(rt, qry);
    for (int i = 1; i <= q; ++i) std::cout << ans[i] << "\n";
    return 0;
}

详细

Test #1:

score: 100
Accepted
time: 0ms
memory: 15740kb

input:

4
1 9
1 8
1 0
9 9 9
6
1 2
1 3
1 4
2 3
2 4
3 4

output:

9
8
0
9
9
8

result:

ok 6 numbers

Test #2:

score: 0
Accepted
time: 0ms
memory: 15816kb

input:

11
1 9
1 8
3 0
4 7
4 1
3 6
1 0
8 7
8 1
10 6
0 0 0 0 0 0
21
1 2
1 3
1 4
1 5
1 6
1 7
1 8
1 9
1 10
1 11
7 1
8 2
9 3
10 4
11 5
1 6
2 7
3 8
4 9
5 10
6 11

output:

7
8
8
7
7
7
0
7
1
7
7
7
1
7
0
7
0
8
1
6
0

result:

ok 21 numbers

Test #3:

score: 0
Accepted
time: 0ms
memory: 18096kb

input:

11
1 9
1 8
3 0
4 7
4 1
3 6
1 0
8 7
8 1
10 6
1000000000000 1000000000000 1000000000000 1000000000000 1000000000000 1000000000000
21
1 2
1 3
1 4
1 5
1 6
1 7
1 8
1 9
1 10
1 11
7 1
8 2
9 3
10 4
11 5
1 6
2 7
3 8
4 9
5 10
6 11

output:

9
8
8
15
9
14
0
7
1
7
14
9
15
9
22
9
23
8
15
16
16

result:

ok 21 numbers

Test #4:

score: -100
Runtime Error

input:

99998
1 683940
1 335116
3 198362
4 28825
5 625394
6 314200
7 270653
8 61629
9 650997
10 693039
11 159577
12 466708
13 715788
14 262771
15 615302
16 1457
17 650381
18 542652
19 101993
20 197937
21 474452
22 859631
23 327526
24 705522
25 500710
26 595050
27 577264
28 955258
29 269967
30 4012
31 471435...

output:


result: