제출 #965607

#	제출 시각	아이디	문제	언어	결과	실행 시간	메모리
965607		steveonalex	자매 도시 (APIO20_swap)	C++17	100 / 100	517 ms	51980 KiB

swap

#include <bits/stdc++.h>
#include "swap.h"
 
using namespace std;
 
typedef long long ll;
typedef unsigned long long ull;
 
#define ALL(v) (v).begin(), (v).end()
#define MASK(i) (1LL << (i))
#define GETBIT(mask, i) (((mask) >> (i)) & 1)
 
// mt19937_64 rng(chrono::steady_clock::now().time_since_epoch().count());
mt19937_64 rng(1);
ll rngesus(ll l, ll r){return ((ull) rng()) % (r - l + 1) + l;}
 
ll max(ll a, ll b){return (a > b) ? a : b;}
ll min(ll a, ll b){return (a < b) ? a : b;}
 
ll LASTBIT(ll mask){return mask & (-mask);}
ll pop_cnt(ll mask){return __builtin_popcountll(mask);}
ll ctz(ll mask){return __builtin_ctzll(mask);}
ll clz(ll mask){return __builtin_clzll(mask);}
ll logOf(ll mask){return 63 - clz(mask);}
 
template <class T1, class T2>
    bool minimize(T1 &a, T2 b){
        if (a > b){a = b; return true;}
        return false;
    }
template <class T1, class T2>
    bool maximize(T1 &a, T2 b){
        if (a < b){a = b; return true;}
        return false;
    }
template <class T>
    void printArr(T& a, string separator = " ", string finish = "\n", ostream& out = cout){
        for(auto i: a) out << i << separator;
        out << finish;
    }
template <class T>
    void remove_dup(vector<T> &a){
        sort(ALL(a));
        a.resize(unique(ALL(a)) - a.begin());
    }

struct DSU{
    int n;
    vector<int> parent;

    DSU(int _n){
        n = _n;
        parent.resize(n);
        for(int i = 0; i<n; ++i) parent[i] = i;
    }

    int find_set(int u){return (u == parent[u]) ? u : (parent[u] = find_set(parent[u]));}
    bool join_set(int u, int v){
        u = find_set(u), v = find_set(v);
        if (u != v){
            parent[v] = u;
            return true;
        }
        return false;
    }
};

const int N = 1e5 + 69, M = N * 2, LOG_N = 17, INF = 1e9 + 69;
int n, m;
vector<pair<int, int>> graph[N];
int val[N];
int sz[N], h[N], parent[N][LOG_N], max_path[N][LOG_N], rizz[N][LOG_N];

int dp1[N], dp2[N];

int two_child(int u, int forbid){
    vector<int> S;
    for(pair<int, int> v: graph[u]) {
        if (v.first != forbid) {
            S.push_back(v.second);
        }
        if (S.size() == 2) break;
    }
    if (S.size() < 2) return INF;
    return S.back();
}

void dfs(int u, int p){
    h[u] = (u == p) ? 1 : (h[p] + 1);
    sz[u] = 1;
    for(int j = 1; MASK(j) < h[u]; ++j){
        int prev = parent[u][j-1];
        parent[u][j] = parent[prev][j-1];
        max_path[u][j] = max(max_path[u][j-1], max_path[prev][j-1]);
        rizz[u][j] = min(rizz[u][j-1], rizz[prev][j-1]);
    }

    int mi = INF, secondMi = INF;
    for(pair<int, int> v: graph[u]) if (v.first != p){
        if (mi > v.second){
            secondMi = mi;
            mi = v.second;
        }
        else minimize(secondMi, v.second);
    }

    dp1[u] = two_child(u, parent[u][0]);

    for(pair<int, int> v: graph[u]) if (v.first != p && v.first >= 0){
        parent[v.first][0] = u;
        max_path[v.first][0] = v.second;
        if (v.second == mi) rizz[v.first][0] = secondMi;
        else rizz[v.first][0] = mi;

        dfs(v.first, u);
        sz[u] += sz[v.first];
        minimize(dp1[u], max(dp1[v.first], v.second));
    }
}

void dfs2(int u, int p){
    if (h[u] > 1){
        minimize(dp2[u], two_child(parent[u][0], u));
    }

    int mi = INF, secondMi = INF;
    for(pair<int, int> v: graph[u]) if (v.first != p){
        int val = max(v.second, dp1[v.first]);
        if (mi > val){
            secondMi = mi;
            mi = val;
        }
        else minimize(secondMi, val);
    }

    for(pair<int, int> v: graph[u]) if (v.first != p && v.first >= 0){
        int val = max(v.second, dp1[v.first]);
        minimize(dp2[v.first], max(dp2[u], max_path[u][0]));
        if (val == mi) minimize(dp2[v.first], secondMi);
        else minimize(dp2[v.first], mi);

        dfs2(v.first, u);
    }
}

int LCA(int u, int v){
    if (h[u] < h[v]) swap(u, v);
    int diff = h[u] - h[v];
    for(int j = 0; j < LOG_N; ++j) if (GETBIT(diff, j)) 
        u = parent[u][j];
    if (u == v) return u;
    for(int j = LOG_N - 1; j>=0; --j) if (parent[u][j] != parent[v][j]){
        u = parent[u][j];
        v = parent[v][j];
    }
    return parent[u][0];
}

void init(int _n, int _m, vector<int> U, vector<int> V, vector<int> W) {
    n = _n, m = _m;
    vector<array<int, 3>> e;
    for(int i = 0; i<m; ++i) e.push_back({{U[i], V[i], W[i]}});
    sort(ALL(e), [](array<int, 3> x, array<int, 3> y){return x[2] < y[2];});

    DSU mst(n);
    vector<array<int, 3>> outlier;
    for(auto i: e){
        int u= i[0], v = i[1], w = i[2];
        if (mst.join_set(i[0], i[1])) {
            graph[u].push_back({v, w});
            graph[v].push_back({u, w});
        }
        else {
            outlier.push_back(i);
            graph[u].push_back({-1, w});
            graph[v].push_back({-1, w});
        }
    }

    for(int i = 0; i<n; ++i){
        sort(ALL(graph[i]), [](pair<int, int> x, pair<int, int> y){return x.second < y.second;});
    }

    for(int i = 0; i<n; ++i) dp1[i] = dp2[i] = INF;
    dfs(0, 0);
    dfs2(0, 0);

    for(int i = 0; i<n; ++i) val[i] = INF;
    DSU jump(n);
    for(auto i: outlier){
        int u = i[0], v = i[1], w = i[2];

        int lck = LCA(u, v);
        while(h[u] > h[lck]){
            minimize(val[u], w);
            jump.join_set(parent[u][0], u);
            u = jump.find_set(u);
        }

        while(h[v] > h[lck]){
            minimize(val[v], w);
            jump.join_set(parent[v][0], v);
            v = jump.find_set(v);
        }
    }
}

int get_weight(int u, int v, int lck = -1){
    if (lck == -1) lck = LCA(u, v);
    int ans= -1;
    int diff = h[u] - h[lck];
    for(int j = 0; j< LOG_N; ++j) if (GETBIT(diff, j)) {
        maximize(ans, max_path[u][j]);
        u = parent[u][j];
    }
    diff = h[v] - h[lck];
    for(int j = 0; j<LOG_N; ++j) if (GETBIT(diff, j)){
        maximize(ans, max_path[v][j]);
        v = parent[v][j];
    }
    return ans;
}


int get_rizz(int u, int d){
    int ans= INF;
    for(int j = 0; j< LOG_N; ++j) if (GETBIT(d, j)) {
        minimize(ans, rizz[u][j]);
        u = parent[u][j];
    }
    return ans;
}

int binary_lift(int u, int d){
    for(int j = 0; j < LOG_N; ++j) if (GETBIT(d, j)) 
        u = parent[u][j];
    return u;
}


int getMinimumFuelCapacity(int x, int y) {
    if (h[x] > h[y]) swap(x, y);
    int lck = LCA(x, y);
    int lim = get_weight(x, y, lck);

    int ans = INF;
    if (lck == x){
        int _x = binary_lift(y, h[y] - h[x] - 1);
        int t1 = dp2[_x], t2 = dp1[y];
        minimize(ans, min(t1, t2));
        minimize(ans, val[y]);
        minimize(ans, val[_x]);
        minimize(ans, get_rizz(y, h[y] - h[lck] - 1));
    }
    else{
        int t1 = dp1[x], t2 = dp1[y];
        minimize(ans, min(t1, t2));
        minimize(ans, val[x]); 
        minimize(ans, val[y]);
        minimize(ans, get_rizz(x, h[x] - h[lck] - 1));
        minimize(ans, get_rizz(y, h[y] - h[lck] - 1));
        int _x = binary_lift(x, h[x] - h[lck] - 1);
        int _y = binary_lift(y, h[y] - h[lck] - 1);
        for(pair<int, int> v: graph[lck]) {
            if (v.first == _x || v.first == _y) continue;
            minimize(ans, v.second);
            break;
        } 
    }

    if (ans == INF) return -1;
    maximize(ans, lim);
    return ans;
}


// int main(void){
//     ios::sync_with_stdio(0); cin.tie(0); cout.tie(0);

//     // freopen("input.inp", "r", stdin);

//     int n, m; cin >> n >> m;
//     vector<int> U, V, W;
//     for(int i = 0; i<m; ++i){
//         int u, v, w; cin >> u >> v >> w;
//         U.push_back(u); V.push_back(v); W.push_back(w);
//     }

//     init(n, m, U, V, W);
//     int q; cin >> q;
//     while(q--){
//         int x, y; cin >> x >> y;
//         cout << getMinimumFuelCapacity(x, y) << "\n";
//     }
 
//     return 0;
// }

• Subtask 1: 6 / 6
• Subtask 2: 7 / 7
• Subtask 3: 17 / 17
• Subtask 4: 20 / 20
• Subtask 5: 23 / 23
• Subtask 6: 27 / 27