제출 #594011

#	제출 시각	아이디	문제	언어	결과	실행 시간	메모리
594011		keta_tsimakuridze	Simurgh (IOI17_simurgh)	C++14	100 / 100	229 ms	79272 KiB

simurgh

#include "simurgh.h"
#include<bits/stdc++.h>
#define pii pair<int,int>
#define f first
#define s second
using namespace std;
const int N = 1e6 + 5;
int f[N], t[N], CNT, P[N], h[N], Nn, up[N], imp[N], p[N];
pii mn[N];
vector<int> golden;
vector<pii> V[N], adj[N], E;
vector<int> edges, x[N];
void dfs0(int u, int p) {
    f[u] = 1;
    for(int i = 0; i < V[u].size(); i++) {
        if(V[u][i].f == p) continue;
        if(!f[V[u][i].f]) {
            dfs0(V[u][i].f, u); //cout << "++" << V[u][i].s << endl;
            edges.push_back(V[u][i].s);
            t[V[u][i].s] = 1;
        }
    }
}
int rem(int e1, int e2) {
    vector<int> x;
    for(int i = 0; i < edges.size(); i++) {
        if(e1 != edges[i]) x.push_back(edges[i]);
    }
    x.push_back(e2);
    return count_common_roads(x) - CNT;
}
void add(int a, int b, int x) {
    adj[a].push_back({b, x});
    adj[b].push_back({a, -x});
}
void dfs(int u, int p) {
    mn[u] = {Nn + 1, 0};
    P[u] = p;
    if(u) h[u] = h[p] + 1; //cout << u << endl;
    for(int i = 0; i < V[u].size(); i++) {
        int e = V[u][i].s, v = V[u][i].f;
        if(v == p) continue;
        if(t[e]) {
            up[v] = e;
            dfs(v, u);
            if(mn[v].f > h[u]) golden[e] = 1;
            else add(e, mn[v].s, rem(e, mn[v].s)), imp[mn[v].s] = 1;
            mn[u] = min(mn[u], mn[v]);
        } else {
            if(h[v] > h[u] && imp[e]) {
            int x = v;
            while(P[x] != u) {
                x = P[x];
            }
            add(up[x], e, rem(up[x], e));
            }
            if(h[v] < h[u]) mn[u] = min(mn[u], {h[v], e});
        }

    }
}
int find(int u) {
    return (p[u] == u ? u : p[u] = find(p[u]));
}
void merge(int u, int v) {
    u = find(u), v = find(v);
    p[u] = v;
}
int ask(vector<int> x, int mid) {
    for(int i = 0; i < Nn; i++) {
        p[i] = i;
    }
    vector<int> v;
    for(int i = 0; i < mid; i++) v.push_back(x[i]), merge(E[x[i]].f, E[x[i]].s);
    int c = 0;
    for(int i = 0; i < edges.size(); i++) {
        if(find(E[edges[i]].f) != find(E[edges[i]].s)) {
            v.push_back(edges[i]);
            merge(E[edges[i]].f, E[edges[i]].s);
            c += golden[edges[i]];
        }
    }
    return count_common_roads(v) - c;
}
std::vector<int> find_roads(int nn, std::vector<int> u, std::vector<int> vv) {
    int m = u.size(); Nn = nn;
    golden.resize(m);
    for(int i = 0; i < m; i++) {
        V[u[i]].push_back({vv[i], i});
        V[vv[i]].push_back({u[i], i});
        E.push_back({vv[i], u[i]});
    }
    dfs0(0, -1);
    CNT = count_common_roads(edges);
    dfs(0, -1);
    vector<int> vis(m);
    for(int i = 0; i < m; i++) {
        if(!vis[i]) {
            queue<int> q;
            q.push(i);
            h[i] = 0;
            int mx = 0, mn = 0;
            vector<int> x;
            while(q.size()) {
                int u = q.front(); q.pop();
                mx = max(mx, h[u]); mn = min(mn, h[u]);
                for(int j = 0; j < adj[u].size(); j++) {
                    if(vis[adj[u][j].f]) continue;
                    h[adj[u][j].f] = h[u] + adj[u][j].s;
                    vis[adj[u][j].f] = 1;
                    q.push(adj[u][j].f);
                }
                x.push_back(u);
            }
            if(mn == mx) continue;
            for(int j = 0; j < x.size(); j++) if(h[x[j]] == mx) golden[x[j]] = 1;
        }
    }
    for(int i = 0; i < m; i++) {
        if(t[i]) continue;
        x[min(u[i], vv[i])].push_back(i);
    }
    for(int i = 0; i < Nn; i++) {
        int cn = ask(x[i], x[i].size());// cout << cn << " _ " << i << endl;
        int L = 0;
        for(int j = 1; j <= cn; j++) {
            int l = L, r = (int)x[i].size() - 1, id = 0;
            while(l <= r) {
                int mid = (l + r) / 2;

                if(ask(x[i], mid + 1) >= j) id = mid, r = mid - 1;
                else l = mid + 1;
            }
            golden[x[i][id]] = 1;
            L = id + 1;
        }
    }

    vector<int> ans;
    for(int i = 0; i < m; i++) if(golden[i]) ans.push_back(i);
    return ans;
}

컴파일 시 표준 에러 (stderr) 메시지

simurgh.cpp: In function 'void dfs0(int, int)':
simurgh.cpp:15:22: warning: comparison of integer expressions of different signedness: 'int' and 'std::vector<std::pair<int, int> >::size_type' {aka 'long unsigned int'} [-Wsign-compare]
   15 |     for(int i = 0; i < V[u].size(); i++) {
      |                    ~~^~~~~~~~~~~~~
simurgh.cpp: In function 'int rem(int, int)':
simurgh.cpp:26:22: warning: comparison of integer expressions of different signedness: 'int' and 'std::vector<int>::size_type' {aka 'long unsigned int'} [-Wsign-compare]
   26 |     for(int i = 0; i < edges.size(); i++) {
      |                    ~~^~~~~~~~~~~~~~
simurgh.cpp: In function 'void dfs(int, int)':
simurgh.cpp:40:22: warning: comparison of integer expressions of different signedness: 'int' and 'std::vector<std::pair<int, int> >::size_type' {aka 'long unsigned int'} [-Wsign-compare]
   40 |     for(int i = 0; i < V[u].size(); i++) {
      |                    ~~^~~~~~~~~~~~~
simurgh.cpp: In function 'int ask(std::vector<int>, int)':
simurgh.cpp:76:22: warning: comparison of integer expressions of different signedness: 'int' and 'std::vector<int>::size_type' {aka 'long unsigned int'} [-Wsign-compare]
   76 |     for(int i = 0; i < edges.size(); i++) {
      |                    ~~^~~~~~~~~~~~~~
simurgh.cpp: In function 'std::vector<int> find_roads(int, std::vector<int>, std::vector<int>)':
simurgh.cpp:107:34: warning: comparison of integer expressions of different signedness: 'int' and 'std::vector<std::pair<int, int> >::size_type' {aka 'long unsigned int'} [-Wsign-compare]
  107 |                 for(int j = 0; j < adj[u].size(); j++) {
      |                                ~~^~~~~~~~~~~~~~~
simurgh.cpp:116:30: warning: comparison of integer expressions of different signedness: 'int' and 'std::vector<int>::size_type' {aka 'long unsigned int'} [-Wsign-compare]
  116 |             for(int j = 0; j < x.size(); j++) if(h[x[j]] == mx) golden[x[j]] = 1;
      |                            ~~^~~~~~~~~~

• Subtask 1: 13 / 13
• Subtask 2: 17 / 17
• Subtask 3: 21 / 21
• Subtask 4: 19 / 19
• Subtask 5: 30 / 30