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IDProblemSubmitterResultTimeMemoryLanguageFile sizeSubmit timeJudge time
#579872#7103. Red Black Treexuanbac05AC ✓1025ms30052kbC++173.1kb2024-09-21 18:47:462024-09-21 18:47:46

Judging History

你现在查看的是最新测评结果

  • [2024-09-21 18:47:46]
  • 评测
  • 测评结果:AC
  • 用时:1025ms
  • 内存:30052kb
  • [2024-09-21 18:47:46]
  • 提交

answer

#include <bits/stdc++.h>
#define ll long long
#define fi first
#define se second
#define endl '\n'
#define MASK(i) (1LL << (i))
#define ull unsigned long long
#define ld long double
#define pb push_back
#define all(x) (x).begin() , (x).end()
#define BIT(x , i) ((x >> (i)) & 1)
#define TASK "task"
#define sz(s) (int) (s).size()
 
using namespace std;
const int mxN = 2e5 + 227;
const int inf = 1e9 + 277;
const int mod = 1e9 + 7;
const ll infll = 1e15 + 7;
const int base = 307;
const int LOG = 20;
 
template <typename T1, typename T2> bool minimize(T1 &a, T2 b) {
    if (a > b) {a = b; return true;} return false;
}
template <typename T1, typename T2> bool maximize(T1 &a, T2 b) {
    if (a < b) {a = b; return true;} return false;
}
 
int n;
int m;
int q;
int a[mxN];
int dep[mxN];
int par[mxN][LOG + 1];
bool red[mxN];
ll dist[mxN];
pair<ll, int> best[mxN];
vector<pair<int, int>> adj[mxN];
int timer = 0;

void dfs(int u, int p, int cur = -1) {
    if(red[u] == true) cur = u;
    for(auto it : adj[u]) {
        int v = it.fi;
        int c = it.se;
        if(v == p) continue;
        dist[v] = dist[u] + c;
        dep[v] = dep[u] + 1;
        par[v][0] = u;
        dfs(v, u, cur);
    }

    best[u] = make_pair(dist[u] - dist[cur], cur);
}


int getlca(int u, int v) {
    if(dep[u] < dep[v]) swap(u, v);
    for(int j = LOG; j >= 0; j--) if(dep[par[u][j]] >= dep[v]) u = par[u][j];
    if(u == v) return u;
    for(int j = LOG; j >= 0; j--) {
        if(par[u][j] != par[v][j]) {
            u = par[u][j];
            v = par[v][j];
        }
    }
    return par[u][0];
}

bool cmp(int x, int y) {
    return best[x].fi > best[y].fi;
}
 
void solve()
{
    cin >> n >> m >> q;
    for(int i = 1; i <= m; i++) {
        int x; cin >> x;
        red[x] = true;
    }
    for(int i = 1; i < n; i++) {
        int u, v, c;
        cin >> u >> v >> c;
        adj[u].pb({v, c});
        adj[v].pb({u, c});
    }

    par[1][0] = 1;
    dfs(1, -1);
    

    for (int j = 1; j <= LOG; j++)
    for (int i = 1; i <= n; i++) par[i][j] = par[par[i][j - 1]][j - 1];

    while(q--) {
        int k; cin >> k;
        ll res = -infll;
        vector<int> node;
        for(int i = 1; i <= k; i++) {
            int x; cin >> x;
            node.pb(x);
            maximize(res, best[x].fi);
        }

        sort(all(node), cmp);

        int lca = node[0];
        ll maxDist = dist[node[0]];
        for(int i = 0; i < sz(node); i++) {
            lca = getlca(lca, node[i]);
            maximize(maxDist, dist[node[i]]);
            if(i + 1 < sz(node)) minimize(res, max(maxDist - dist[lca], best[node[i + 1]].fi));
            else minimize(res, maxDist - dist[lca]);
        }
        cout << res << endl;
    }
    for(int u = 1; u <= n; u++) {
        adj[u].clear();
        red[u] = false;
    }
}
 
int main()
{
    ios_base::sync_with_stdio(false);
    cin.tie(nullptr);
    // freopen(TASK".inp" , "r" , stdin);
    // freopen(TASK".out" , "w" , stdout);
 
    int tc = 1;
    cin >> tc;
    while(tc--) {
        solve();
    }
    return 0;
}

这程序好像有点Bug,我给组数据试试?

Details

Tip: Click on the bar to expand more detailed information

Test #1:

score: 100
Accepted
time: 2ms
memory: 11880kb

input:

2
12 2 4
1 9
1 2 1
2 3 4
3 4 3
3 5 2
2 6 2
6 7 1
6 8 2
2 9 5
9 10 2
9 11 3
1 12 10
3 3 7 8
4 4 5 7 8
4 7 8 10 11
3 4 5 12
3 2 3
1 2
1 2 1
1 3 1
1 1
2 1 2
3 1 2 3

output:

4
5
3
8
0
0
0

result:

ok 7 lines

Test #2:

score: 0
Accepted
time: 1025ms
memory: 30052kb

input:

522
26 1 3
1
1 4 276455
18 6 49344056
18 25 58172365
19 9 12014251
2 1 15079181
17 1 50011746
8 9 2413085
23 24 23767115
22 2 26151339
26 21 50183935
17 14 16892041
9 26 53389093
1 20 62299200
24 18 56114328
11 2 50160143
6 26 14430542
16 7 32574577
3 16 59227555
3 15 8795685
4 12 5801074
5 20 57457...

output:

148616264
148616264
0
319801028
319801028
255904892
317070839
1265145897
1265145897
1072765445
667742619
455103436
285643094
285643094
285643094
317919339
0
785245841
691421476
605409472
479058444
371688030
303203698
493383271
919185207
910180170
919185207
121535083
181713164
181713164
181713164
181...

result:

ok 577632 lines

Extra Test:

score: 0
Extra Test Passed