제출 #414174

#	제출 시각	아이디	문제	언어	결과	실행 시간	메모리
414174		ACmachine	자매 도시 (APIO20_swap)	C++17	0 / 100	2087 ms	25952 KiB

swap

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

#define FOR(i, j, k, l) for(int i = (j); i < (k); i += (l))
#define FORD(i, j, k, l) for(int i = (j); i>=(k); i -= (l))
#define REP(i, n) FOR(i, 0, n, 1)
#define REPD(i, n) FORD(i, n, 0, 1)
#define pb push_back
typedef long long ll;
const int INF = (int)1e9 + 7;
const ll INFF = (ll)1e18;
struct dsu{
    vector<int> p;
    dsu(int n){
        p.resize(n, -1);
    }
    int find(int x){
        return (p[x] < 0 ? x : p[x] = find(p[x]));
    }
    bool same_set(int u, int v){
        return find(u) == find(v);
    }
    bool join(int u, int v){
        u = find(u);
        v = find(v);
        if(u == v)
            return false;
        if(-p[u] < -p[v])
            swap(u, v);
        p[u] += p[v]; p[v] = u;
        return true;
    }
};
// mstpath + dalsia cesta z X do Y bez mstpath edges
// mstpath + neico s deg 3
int n, m;
vector<bool> on_path;
vector<vector<array<int, 2>>> g; // mst;
vector<vector<int>> g_id;
vector<vector<array<int, 2>>> initg; 
bool fn = false;
void dfs(int v, int p, int dest, int ep){
    if(ep != -1 && !fn) 
        on_path[ep] = true;
    if(v == dest){
        fn = true;
        return;
    }
    REP(i, g[v].size()){
        if(fn) return;
        if(g[v][i][0] == p) 
            continue; 
        dfs(g[v][i][0], v, dest, g_id[v][i]);
    } 
    if(fn) return; 
    if(ep != -1)
        on_path[ep] = false; 
}
vector<array<int, 3>> edges;
vector<int> dist;
void get_dist(int v, int p, int w){
    dist[v] = w;
    for(auto x : g[v]){
        if(x[0] == p) 
            continue;
        get_dist(x[0], v, max(w, x[1]));
    }
}
void init(int N, int M, std::vector<int> U, std::vector<int> V, std::vector<int> W) {
    n = N; m = M;
    g.resize(n); initg.resize(n);
    g_id.resize(n);
    dist.resize(n);
    REP(i, m){
        initg[U[i]].pb({V[i], W[i]});
        initg[V[i]].pb({U[i], W[i]});
        edges.pb({W[i], U[i], V[i]});
    }
    sort(edges.begin(), edges.end());
    dsu d(n);
    int id = 0;
    for(auto e : edges){
        if(d.same_set(e[1], e[2])) 
            continue;
        g[e[1]].pb({e[2], e[0]});
        g[e[2]].pb({e[1], e[0]});
        g_id[e[1]].pb(id);
        g_id[e[2]].pb(id);
        d.join(e[1], e[2]);
        id++;
    }
    auto cmp = [&](array<int, 2> f, array<int, 2> s){
        return f[1] < s[1];
    };
    REP(i, n){
        sort(initg[i].begin(), initg[i].end(), cmp);
    }
}

int getMinimumFuelCapacity(int X, int Y) {
    vector<int> distf, dists;
    get_dist(X, -1, -INF);
    distf = dist;
    get_dist(Y, -1, -INF);
    dists = dist;
    fn = false;
    on_path = vector<bool>(m, false);
    dfs(X, -1, Y, -1);
    int ans = INF;
    int id = 0;
    dsu d(n); 
    if(m != n - 1){
        for(auto e : edges){
            //cout << X << " " << Y << " " << id << " " << on_path[id] << "\n";
            if(on_path[id]){
                id++;
                continue;
            }
            d.join(e[1], e[2]);
            if(d.same_set(X, Y)){
                ans = min(ans, max(e[0], distf[Y]));
                break;
            }
            id++;
        }
    }
    REP(i, n){
        if(initg[i].size() > 2){
            ans = min(ans, max({distf[Y], distf[i], dists[i], initg[i][2][1]}));
        }
    }
    if(ans == INF){
        return -1;
    }
    return ans;

    return 0;
}

컴파일 시 표준 에러 (stderr) 메시지

swap.cpp: In function 'void dfs(int, int, int, int)':
swap.cpp:5:44: warning: comparison of integer expressions of different signedness: 'int' and 'std::vector<std::array<int, 2> >::size_type' {aka 'long unsigned int'} [-Wsign-compare]
    5 | #define FOR(i, j, k, l) for(int i = (j); i < (k); i += (l))
      |                                            ^
swap.cpp:7:19: note: in expansion of macro 'FOR'
    7 | #define REP(i, n) FOR(i, 0, n, 1)
      |                   ^~~
swap.cpp:50:5: note: in expansion of macro 'REP'
   50 |     REP(i, g[v].size()){
      |     ^~~

• Subtask 1: 0 / 6
• Subtask 2: 0 / 7
• Subtask 3: 0 / 17
• Subtask 4: 0 / 20
• Subtask 5: 0 / 23
• Subtask 6: 0 / 27