Submission #567513

# Submission time Handle Problem Language Result Execution time Memory
567513 2022-05-23T15:53:03 Z Stickfish Swapping Cities (APIO20_swap) C++17
0 / 100
123 ms 16080 KB
#include "swap.h"
#include <vector>
#include <algorithm>
using namespace std;

const int MAXN = 1e5 + 123;
const int INF = 1e9 + 177013;
vector<pair<int, int>> edg[MAXN];
vector<pair<int, int>> edg_mst[MAXN];
int depth[MAXN];
int timer = 0;
int tin[MAXN];
int tout[MAXN];
pair<int, int> rt[MAXN];
int rt_deviate[MAXN];
pair<int, int> crt[MAXN];
int crt_deviate[MAXN];

pair<int, int> min_deviation(int v, vector<int> vc) {
    for (auto [u, w] : edg_mst[v]) {
        bool isok = true;
        for (auto t : vc) {
            if (t == u) {
                isok = false;
                break;
            }
        }
        if (isok)
            return {u, w};
    }
    return {-1, INF};
}

void dfs(int v) {
    tin[v] = timer++;
    int rtv = rt[v].first;
    int crtrtv = crt[rtv].first;
    int crtcrtrtv = crt[crtrtv].first;
    if (depth[rtv] - depth[crtrtv] == depth[crtrtv] - depth[crtcrtrtv]) {
        crt[v] = {crtcrtrtv, max({rt[v].second, crt[rtv].second, crt[crtrtv].second})};
        crt_deviate[v] = min({rt_deviate[v], crt_deviate[rtv], crt_deviate[crtrtv]});
    }
    for (auto [u, w] : edg_mst[v]) {
        if (u == rt[v].first)
            continue;
        rt[u] = {v, w};
        rt_deviate[u] = min_deviation(v, vector<int>{u, rt[v].first}).second;
        depth[u] = depth[v] + 1;
    }
    tout[v] = timer;
}

struct dsu {
    void resize(int n) {
        par.resize(n);
        sz.assign(n, 1);
        for (int i = 0; i < n; ++i)
            par[i] = i;
    }

    int gst(int i) {
        if (par[i] == i)
            return i;
        return par[i] = gst(par[i]);
    }

    bool unite(int i, int j) {
        i = gst(i);
        j = gst(j);
        if (i == j)
            return false;
        if (sz[i] < sz[j])
            swap(i, j);
        par[j] = i;
        sz[i] += sz[j];
        return true;
    }
 private:
     vector<int> par;
     vector<int> sz;
};

pair<int, int> get_up(int v, int d) {
    int ans = 0;
    while (depth[v] > d) {
        if (depth[crt[v].first] >= d) {
            ans = max(ans, crt[v].second);
            v = crt[v].first;
        } else {
            ans = max(ans, rt[v].first);
            v = rt[v].first;
        }
    }
    return {v, ans};
}

pair<int, pair<int, int>> lca(int v, int u) {
    pair<int, int> ans(0, 0);
    if (depth[u] > depth[v]) {
        pair<int, int> p = get_up(u, depth[v]);
        ans.second = p.second;
        u = p.first;
    }
    if (depth[u] < depth[v]) {
        pair<int, int> p = get_up(v, depth[u]);
        ans.first = p.second;
        v = p.first;
    }
    while (v != u) {
        if (crt[v].first == crt[u].first) {
            ans.first = max(ans.first, rt[v].second);
            v = rt[v].first;
            ans.second = max(ans.second, rt[u].second);
            u = rt[u].first;
        } else {
            ans.first = max(ans.first, crt[v].second);
            v = crt[v].first;
            ans.second = max(ans.second, crt[u].second);
            u = crt[u].first;
        }
    }
    return {v, ans};
}

void init(int n, int m, vector<int> U, vector<int> V, vector<int> W) {
    vector<pair<int, pair<int, int>>> edg_weight(m);
    for (int i = 0; i < m; ++i) {
        edg_weight[i] = {W[i], {U[i], V[i]}};
    }
    sort(edg_weight.begin(), edg_weight.end());
    dsu su;
    su.resize(n);
    for (auto [w, e] : edg_weight) {
        auto [u, v] = e;
        if (su.unite(u, v)) {
            edg_mst[u].push_back({v, w});
            edg_mst[v].push_back({u, w});
        }
    }
    dfs(0);
}

pair<int, int> get_up_deviate(int v, int d) {
    int ans = INF;
    while (depth[v] > d) {
        if (depth[crt[v].first] >= d) {
            ans = min(ans, crt_deviate[v]);
            v = crt[v].first;
        } else{
            ans = max(ans, rt_deviate[v]);
            v = rt[v].first;
        }
    }
    return {v, ans};
}

int getMinimumFuelCapacity(int X, int Y) {
    auto [a, p] = lca(X, Y);
    int ans = max(p.first, p.second);
    int ans0 = INF;
    auto [u, wu] = get_up_deviate(X, depth[a] + 1);
    auto [v, wv] = get_up_deviate(Y, depth[a] + 1);
    ans0 = min(wu, wv);
    if (X != a && Y != a) {
        ans0 = min(ans0, min_deviation(a, vector<int>{u, v}).second);
    }
    if (ans0 == INF)
        return -1;
    return max(ans, ans0);
}
# Verdict Execution time Memory Grader output
1 Correct 2 ms 4948 KB Output is correct
2 Correct 3 ms 4996 KB Output is correct
3 Correct 2 ms 4948 KB Output is correct
4 Incorrect 3 ms 5004 KB Output isn't correct
5 Halted 0 ms 0 KB -
# Verdict Execution time Memory Grader output
1 Correct 2 ms 4948 KB Output is correct
2 Correct 3 ms 4996 KB Output is correct
3 Incorrect 123 ms 16080 KB Output isn't correct
4 Halted 0 ms 0 KB -
# Verdict Execution time Memory Grader output
1 Correct 2 ms 4948 KB Output is correct
2 Correct 3 ms 4996 KB Output is correct
3 Correct 2 ms 4948 KB Output is correct
4 Incorrect 3 ms 5004 KB Output isn't correct
5 Halted 0 ms 0 KB -
# Verdict Execution time Memory Grader output
1 Correct 2 ms 4948 KB Output is correct
2 Correct 3 ms 4996 KB Output is correct
3 Correct 2 ms 4948 KB Output is correct
4 Incorrect 3 ms 5004 KB Output isn't correct
5 Halted 0 ms 0 KB -
# Verdict Execution time Memory Grader output
1 Correct 2 ms 4948 KB Output is correct
2 Correct 3 ms 4996 KB Output is correct
3 Correct 2 ms 4948 KB Output is correct
4 Incorrect 3 ms 5004 KB Output isn't correct
5 Halted 0 ms 0 KB -
# Verdict Execution time Memory Grader output
1 Correct 2 ms 4948 KB Output is correct
2 Correct 3 ms 4996 KB Output is correct
3 Correct 2 ms 4948 KB Output is correct
4 Incorrect 3 ms 5004 KB Output isn't correct
5 Halted 0 ms 0 KB -