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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
#623594#8235. Top ClusterfosovWA 1296ms150204kbC++142.9kb2024-10-09 13:21:512024-10-09 13:21:51

Judging History

你现在查看的是最新测评结果

  • [2024-10-09 13:21:51]
  • 评测
  • 测评结果:WA
  • 用时:1296ms
  • 内存:150204kb
  • [2024-10-09 13:21:51]
  • 提交

answer

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

#define ll long long 
#define INF 0x3f3f3f3f
#define LNF 0x3f3f3f3f3f3f3f3fll
#define MOD 998244353

#define N 500010
#define lg 20

vector<pair<int, int>> G[N];
pair<int, int> ord[N], dia[N];
int st[lg][N<<1], dep[N], seq[N<<1], fr[N], z;
ll dis[N];

void add_edge(int u, int v, int l) {
    G[u].emplace_back(v, l);
    G[v].emplace_back(u, l);
}

void dfs(int u, int fa, ll pd, int d) {
    fr[u] = z;
    st[0][z ++] = u;
    dis[u] = pd;
    dep[u] = d;

    for (auto [v, l] : G[u]) {
        if (v == fa) continue;
        dfs(v, u, pd+l, d+1);
        st[0][z ++] = u;
    }
}

void init() {
    for (int i = 1; i < lg; ++ i) {
        for (int j = 0; j + (1 << i) <= z; ++ j) {
            int l = j, r = j + (1 << (i-1));
            st[i][j] = dep[st[i-1][l]] < dep[st[i-1][r]] ? st[i-1][l] : st[i-1][r];
        }
    }
}

int lca(int u, int v) {
    if (fr[u] > fr[v]) swap(u, v);
    int lgn = ceil(log2(fr[v] - fr[u] + 1));
    int l = fr[u], r = fr[v] - (1 << lgn) + 1;
    return dep[st[lgn][l]] < dep[st[lgn][r]] ? st[lgn][l] : st[lgn][r];
}

ll distance(int u, int v) {
    int r = lca(u, v);
    return dis[u] + dis[v] - 2ll * dis[r];
}

int main() {
#ifdef TEST
    freopen("zz.in", "r+", stdin);
#endif
    ios::sync_with_stdio(0);
    cin.tie(0);
    cout.tie(0);

    int n, q; cin >> n >> q;
    int dw = -1;
    set<int> wset;
    for (int i = 1; i <= n; ++ i) {
        int w; cin >> w;
        wset.insert(w);
        ord[i] = make_pair(w, i);
    }
    for (int i = 0; i <= n; ++ i) {
        if (wset.find(i) == wset.end()) {
            dw = i;
            break;
        }
    }
    assert(dw != -1);
    
    sort(ord+1, ord+1+n);
    dia[1] = make_pair(ord[1].second, ord[1].second);

    for (int i = 0; i < n-1; ++ i) {
        int u, v, l; cin >> u >> v >> l;
        add_edge(u, v, l);
    }

    dfs(1, 1, 0, 0);
    init();
    
    for (int i = 2; i <= n; ++ i) {
        auto [pn0, pn1] = dia[i-1];
        auto [_, cn] = ord[i];

        ll d0 = distance(pn0, pn1);
        ll d1 = distance(pn0, cn);
        ll d2 = distance(pn1, cn);

        dia[i] = dia[i-1];
        if (d0 < d1) dia[i] = make_pair(pn0, cn), d0 = d1;
        if (d0 < d2) dia[i] = make_pair(pn1, cn), d0 = d2;
    }

    auto in_range = [&](int r, int x, ll k) {
        auto [n0, n1] = dia[r];
        return max(distance(n0, x), distance(n1, x)) <= k;
    };

    while (q --) {
        ll x, k; cin >> x >> k;
        int l = 1, r = n+1;
        while (l < r) {
            int m = (l + r) / 2;
            if (in_range(m, x, k)) {
                l = m+1;
            } else {
                r = m;
            }
        }
        // assert(!in_range(l, x, k));

        int res = l == n+1 ? dw : min(dw, ord[l].first);
        cout << res << '\n';
    }
}

詳細信息

Test #1:

score: 100
Accepted
time: 3ms
memory: 29844kb

input:

5 4
3 9 0 1 2
1 2 10
3 1 4
3 4 3
3 5 2
3 0
1 0
4 6
4 7

output:

1
0
3
4

result:

ok 4 number(s): "1 0 3 4"

Test #2:

score: -100
Wrong Answer
time: 1296ms
memory: 150204kb

input:

500000 500000
350828 420188 171646 209344 4 999941289 289054 79183 999948352 427544 160827 138994 192204 108365 99596 999987124 292578 2949 384841 269390 999920664 315611 163146 51795 265839 34188 999939494 145387 366234 86466 220368 357231 347706 332064 279036 173185 5901 217061 112848 37915 377359...

output:

0
249999
249999
249999
249999
249999
249999
249999
249999
249999
249999
249999
249999
249999
249999
249999
249999
249999
249999
249999
249999
249999
249999
249999
249999
249999
249999
249999
249999
249999
249999
249999
249999
249999
249999
249999
249999
249999
249999
249999
249999
249999
249999
2499...

result:

wrong answer 20939th numbers differ - expected: '4', found: '0'