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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
#386917#5102. Dungeon CrawlerEnergy_is_not_over#WA 1ms3804kbC++173.9kb2024-04-11 21:27:212024-04-11 21:27:23

Judging History

你现在查看的是最新测评结果

  • [2024-04-11 21:27:23]
  • 评测
  • 测评结果:WA
  • 用时:1ms
  • 内存:3804kb
  • [2024-04-11 21:27:21]
  • 提交

answer

//
// Stvoreno ENERGom o 11.04.24. 13:44:56
//

#include <bits/stdc++.h>

#define all(a) a.begin(),a.end()
#define len(a) (int)(a.size())
#define F first
#define fir first
#define S second
#define sec second
#define mp make_pair
#define MP make_pair
#define pb push_back
#define PB push_back

using namespace std;

typedef pair<int, int> pii;
typedef long long ll;
typedef long double ld;

#ifdef Energy
#define DEBUG for (int _____DEBUG=1;_____DEBUG;_____DEBUG=0)

template<class ...Ts>
auto &PRNT(Ts ...ts) { return ((cerr << ts << " "), ...); }

#define LOG(...) PRNT(#__VA_ARGS__" ::",__VA_ARGS__)<<endl
#else
#define DEBUG while (0)
#define LOG(...)
#endif

const int max_n = 2011, max_q = 200111, inf = 1000111222;

vector<pair<int, int>> v[max_n];
int n, cnt_q;
// qind, key, trap
vector<pair<int, pair<int, int>>> q[max_n];
ll ans[max_q];
ll d[max_n];
int tin[max_n];
int tout[max_n];
int cur_t = 0;
vector<pair<int, int>> leaves;
int p[max_n];
bool good[max_n];
int lst_good = -1;

bool is_pr(int a, int b) {
    return tin[a] <= tin[b] && tout[a] >= tout[b];
}
ll SUM = 0;

void dfs(int cur, int pr, ll cur_d) {
    tin[cur] = cur_t++;
    d[cur] = cur_d;
    p[cur] = pr;
//    if (v[cur].size() == 1) {
//        leaves.push_back(cur);
//    }
    for (auto p : v[cur]) {
        int to = p.F, w = p.S;
        if (to == pr) continue;
        dfs(to, cur, cur_d + w);
    }
    tout[cur] = cur_t++;
}

void dfs2(int cur, int pr) {
    int pr_good = lst_good;
    if (good[cur]) {
        lst_good = cur;
    }
    if (v[cur].size() == 1) {
        leaves.emplace_back(cur, lst_good);
    }
    for (auto to : v[cur]) {
        if (to.F != pr) {
            dfs2(to.F, cur);
        }
    }

    lst_good = pr_good;
}

void solve(int root) {
    cur_t = 0;
    dfs(root, -1, 0);
    ll mx_d = 0;
    for (int i = 0; i < n; ++i) {
        mx_d = max(mx_d, d[i]);
    }
    for (auto qq : q[root]) {
        int ind = qq.F;
        int k = qq.S.F, t = qq.S.S;
        if (is_pr(t, k)) {
            ans[ind] = -1;
            continue;
        }
        if (is_pr(k, t)) {
            ans[ind] = SUM - mx_d;
            continue;
        }

        int lca = -1;
        for (int i = 0; i < n; ++i) {
            if (!is_pr(i, k) || !is_pr(i, t)) continue;
            if (lca == -1 || d[i] > d[lca]) {
                lca = i;
            }
        }
        memset(good, 0, sizeof(good));
        good[k] = 1;
        int pk = k;
        while(p[pk] != -1 && is_pr(lca, p[pk])) {
            pk = p[pk];
            good[pk] = 1;
        }
        lst_good = -1;
        leaves.clear();
        dfs2(0, -1);

        ll ans_best = 1e18;
        for (pair<int, int> x : leaves) {
            int l = x.F, g = x.S;
            ll ans_cur;
            if (g == -1) {
                ans_cur = SUM - d[l];
            } else {
                ans_cur = SUM - d[l] + 2 * (d[g] - d[lca]);
            }
            ans_best = min(ans_best, ans_cur);
        }
        ans[ind] = ans_best;
    }
}

int main() {
//    freopen("input_b.txt","r",stdin);
//    freopen("output.txt","w",stdout);
    ios_base::sync_with_stdio(0);
    cin.tie(0);
    cin >> n >> cnt_q;
    for (int i = 0; i + 1< n; ++i) {
        int a, b, w;
        cin >> a >> b >> w;
        --a, --b;
        v[a].emplace_back(b, w);
        v[b].emplace_back(a, w);
        SUM += w;
        SUM += w;
    }
    for (int i = 0; i < cnt_q; ++i) {
        int s, k, t;
        cin >> s >> k >> t;
        --s, --k, --t;
        q[s].emplace_back(i, MP(k, t));
    }
    for (int i = 0; i < n; ++i) {
        solve(i);
    }
    for (int i = 0; i < cnt_q; ++i) {
        if (ans[i] == -1) {
            cout << "impossible\n";
        } else {
            cout << ans[i] << "\n";
        }
    }
    exit(0);
}

详细

Test #1:

score: 100
Accepted
time: 1ms
memory: 3804kb

input:

22 5
1 2 7
2 3 5
3 4 8
3 6 6
3 7 3
2 5 6
5 8 2
8 9 11
2 10 16
1 11 12
11 12 4
11 13 9
1 14 25
14 15 4
15 16 5
15 17 6
15 18 1
15 19 8
14 20 7
20 21 9
20 22 17
1 19 9
1 9 19
1 8 9
1 9 8
2 22 11

output:

316
293
293
impossible
314

result:

ok 5 lines

Test #2:

score: -100
Wrong Answer
time: 1ms
memory: 3728kb

input:

100 100
1 2 289384
2 3 930887
2 4 692778
4 5 636916
4 6 747794
4 7 238336
4 8 885387
8 9 760493
8 10 516650
8 11 641422
8 12 202363
8 13 490028
8 14 368691
8 15 520060
8 16 897764
16 17 513927
16 18 180541
16 19 383427
16 20 89173
16 21 455737
16 22 5212
16 23 595369
16 24 702568
16 25 956430
16 26 ...

output:

103526917
103484292
104479933
104379596
104405611
104775512
104406822
105291604
103838430
103575842
103723810
104175650
105894571
104509242
103971939
105376499
105223283
104153426
105082245
104385328
104130613
104800548
106846555
104138329
103769253
103474724
104044745
104385328
103575842
105460460
...

result:

wrong answer 3rd lines differ - expected: '106288816', found: '104479933'