제출 #293102

#	제출 시각	아이디	문제	언어	결과	실행 시간	메모리
293102		Saboon	Simurgh (IOI17_simurgh)	C++17	70 / 100	234 ms	7800 KiB

simurgh

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

const int maxn = 500 + 10;

vector<pair<int,int>> g[maxn];
int par[maxn], parindex[maxn], h[maxn];
bool visited[maxn];
int Cost, c[maxn*maxn];

void dfs(int v){
    visited[v] = 1;
    for (auto [u,idx] : g[v]){
        if (!visited[u]){
            h[u] = h[v]+1;
            par[u] = v;
            parindex[u] = idx;
            dfs(u);
        }
    }
}

bool eq[maxn];
vector<int> Q;
vector<int> Dw[maxn];
vector<int> Ed[maxn];
int sz[maxn];

void solve(int l, int r, int x){
    if (l >= r)
        return;
    int AllZero = Cost;
    for (int i = l; i < r; i++){
        Q[Dw[x][i]-1] = Ed[x][i];
        AllZero -= c[parindex[Dw[x][i]]];
    }
    int Tmp = count_common_roads(Q);
    for (int i = l; i < r; i++)
        Q[Dw[x][i]-1] = parindex[Dw[x][i]];
    if (Tmp != AllZero){
        if (l+1 == r){
            c[Ed[x][l]] = 1;
            return;
        }
        int mid = (l+r)>>1;
        solve(l,mid,x);
        solve(mid,r,x);
    }
    for (int i = l; i < r; i++)
        Q[Dw[x][i]-1] = parindex[Dw[x][i]];
}

vector<int> find_roads(int n, vector<int> u, vector<int> v){
    int m = v.size();
    for (int i = 0; i < v.size(); i++){
        g[v[i]].push_back({u[i],i});
        g[u[i]].push_back({v[i],i});
    }
    dfs(0);
    Q.resize(n-1);
    for (int i = 1; i < n; i++)
        Q[i-1] = parindex[i];
    Cost = count_common_roads(Q);
    memset(c, -1, sizeof c);
    for (int i = 0; i < m; i++){
        if (h[v[i]] > h[u[i]])
            swap(v[i],u[i]);
        if (par[u[i]] == v[i])
            continue;
        int x = u[i], found = 0, me = -1;
        while (x != v[i]){
            if (c[parindex[x]] == -1)
                found = 1;
            x = par[x];
        }
        if (!found)
            continue;
        x = u[i];
        while (x != v[i]){
            if (c[parindex[x]] != -1 and me != -1){
                x = par[x];
                continue;
            }
            Q[x-1] = i;
            int Tmp = count_common_roads(Q);
            if (c[parindex[x]] != -1){
                if (Tmp == Cost)
                    me = c[parindex[x]];
                else
                    me = 1-c[parindex[x]];
           }
            else{
                if (Tmp == Cost)
                    eq[x] = 1;
                else if (Tmp > Cost)
                    eq[x] = 0, me = 1;
                else
                    eq[x] = 0, me = 0;
            }
            Q[x-1] = parindex[x];
            x = par[x];
        }
        if (me == -1)
            me = 0;
        x = u[i];
        while (x != v[i]){
            if (c[parindex[x]] == -1){
                if (eq[x])
                    c[parindex[x]] = me;
                else
                    c[parindex[x]] = 1-me;
            }
            x = par[x];
        }
        c[i] = me;
    }
    for (int i = 1; i < n; i++)
        c[parindex[i]] = abs(c[parindex[i]]);
    for (int i = 0; i < m; i++){
        if (c[i] != -1)
            continue;
        Dw[sz[u[i]]].push_back(u[i]);
        Ed[sz[u[i]]].push_back(i);
        sz[u[i]] ++;
    }
    for (int i = 0; i < n; i++)
        solve(0, Dw[i].size(), i);
    int now = 0;
    for (int i = 0; i < m; i++)
        if (c[i] == 1)
            Q[now++] = i;
    return Q;
}

컴파일 시 표준 에러 (stderr) 메시지

simurgh.cpp: In function 'std::vector<int> find_roads(int, std::vector<int>, std::vector<int>)':
simurgh.cpp:56:23: warning: comparison of integer expressions of different signedness: 'int' and 'std::vector<int>::size_type' {aka 'long unsigned int'} [-Wsign-compare]
   56 |     for (int i = 0; i < v.size(); i++){
      |                     ~~^~~~~~~~~~

• Subtask 1: 13 / 13
• Subtask 2: 17 / 17
• Subtask 3: 21 / 21
• Subtask 4: 19 / 19
• Subtask 5: 0 / 30