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IDProblemSubmitterResultTimeMemoryLanguageFile sizeSubmit timeJudge time
#408152#8280. Game of Stringslight_ink_dots#RE 0ms0kbC++142.7kb2024-05-09 19:04:242024-05-09 19:04:41

Judging History

你现在查看的是最新测评结果

  • [2024-05-09 19:04:41]
  • 评测
  • 测评结果:RE
  • 用时:0ms
  • 内存:0kb
  • [2024-05-09 19:04:24]
  • 提交

answer

#include <bits/stdc++.h>
using namespace std;

int main() {
    static const int maxn = 50010, maxlg = 20;
    int t;
    scanf("%d", &t);
    while (t--) {
        int n, s, t;
        scanf("%d %d %d", &n, &s, &t);
        static vector<int> G[maxn];
        for (int i = 1; i <= n; i++) G[i].clear();
        for (int i = 1, u, v; i < n; i++) {
            scanf("%d %d", &u, &v);
            G[u].push_back(v);
            G[v].push_back(u);
        }
        if (n == 2) {
            printf("%d %d\n", s, t);
            continue;
        }
        if (n == 3) {
            printf("%d %d %d\n", s, s ^ t, t);
            continue;
        }
        static int lg[maxn], dep[maxn];
        static int dfn[maxn], st[maxlg][maxn], cnt;
        static auto get = [](const int x, const int y) { return dep[x] < dep[y] ? x : y; };
        function<void(int, int)> dfs = [&dfs](const int u, const int fa) {
            st[0][dfn[u] = ++cnt] = fa;
            for (int i : G[u])
                if (i != fa)
                    dep[i] = dep[u] + 1, dfs(i, u);
            return;
        };
        cnt = 0, dfs(1, 0);
        for (int i = 2; i <= n; i++) lg[i] = lg[i >> 1] + 1;
        for (int l = 1; l <= lg[n]; l++)
            for (int i = 1; i + (1 << l) - 1 <= n; i++)
                st[l][i] = get(st[l - 1][i], st[l - 1][i + (1 << (l - 1))]);
        auto dist = [](int u, int v) {
            int ret = dep[u] + dep[v];
            u = dfn[u], v = dfn[v];
            if (u > v)
                swap(u, v);
            int Lg = lg[v - (++u) + 1];
            return ret - (dep[get(st[Lg][u], st[Lg][v - (1 << Lg) + 1])] << 1);
        };
        static int p[maxn], val;
        static int ans[maxn], Val;
        p[1] = s, p[n] = t, val = 0;
        for (int i = 2, x = 1; i < n; i++, x++) {
            while (x == s || x == t) x++;
            p[i] = x;
        }
        static random_device rd;
        static mt19937 rng(rd());
        for (int t = 0; true; t++) {
            shuffle(p + 2, p + n, rng), val = 0;
            for (int i = 1; i < n; i++) val ^= dist(p[i], p[i + 1]);
            if (val < 16)
                break;
        }
        memcpy(ans, p, sizeof(int) * (n + 5)), Val = val;
        for (int t = 0; t < 1000; t++) {
            int id = rng() % (n - 3) + 2;
            for (int i = id; i <= id + 2; i++) val ^= dist(p[i - 1], p[i]);
            swap(p[id], p[id + 1]);
            for (int i = id; i <= id + 2; i++) val ^= dist(p[i - 1], p[i]);
            if (Val > val)
                memcpy(ans, p, sizeof(int) * (n + 5)), Val = val;
        }
        for (int i = 1; i <= n; i++) printf("%d ", ans[i]);
        printf("\n");
    }
    return 0;
}

Details

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Test #1:

score: 0
Runtime Error

input:

abbabbbbabbaaaaabbbaabaaaaaabbbaabbabababaabababaababaaaaaabaaabaaabbbbababaaabbbabababbbabbbaabaaababbbaabaabbaaabbababaaaaabbbaabaaabbaabaabaaabaaabaababaabbbbbbbbabbbbbabbbaabababbaababbbbbabbbbaaabbaabaabaaabbabbaaabbaaababaabbbaabbbaaaabbababbabaababababaaaabbaaaabaabaaaababaaabababbbaaabababbb...

output:


result: