oj.uz

답안 #261318

# 제출 시각 아이디 문제 언어 결과 실행 시간 메모리
261318 2020-08-11T16:12:05 Z doowey 수도 (JOI20_capital_city) C++14
0 / 100
 3000 ms 39388 KB 
#include <bits/stdc++.h>

using namespace std;

typedef long long ll;
typedef pair<int, int> pii;

#define fi first
#define se second
#define mp make_pair
#define fastIO ios::sync_with_stdio(false);cin.tie(0);cout.tie(0);

const int N = (int)2e5 + 100;
vector<int> Z[N];
vector<int> T[N];
int id[N];
bool ban[N];
int par[N];
int subt[N];

bool now[N];

vector<int> mark;

void dfs(int u, int pr){
    subt[u] = 1;
    now[u]=true;
    mark.push_back(u);
    for(auto x : T[u]){
        if(ban[x] || x == pr) continue;
        dfs(x, u);
        subt[u] += subt[x];
    }
}

int up[N];

void dfs1(int u, int pr){
    up[u] = pr;
    for(auto x : T[u]){
        if(ban[x] || x == pr) continue;
        dfs1(x, u);
    }
}

int fin(int u){
    if(par[u]==u)
        return u;
    return par[u]=fin(par[u]);
}

int res;

void decomp(int node){
    mark.clear();
    dfs(1, -1);
    int pr = -1;
    bool is = true;
    int sz = subt[node];
    while(is){
        is = false;
        for(auto x : T[node]){
            if(x == pr || ban[x]) continue;
            if(subt[x] > sz/2){
                pr = node;
                node = x;
                is = true;
                break;
            }
        }
    }
    dfs1(node, node);
    set<int> has, need;
    need.insert(id[node]);
    int cur = 0;
    bool valid = true;
    int hh;
    while(!need.empty() && valid){
        auto it = need.begin();
        cur ++ ;
        for(auto x : Z[(*it)]){
            if(!now[x]){ // big optimization
                valid=false;
                break;
            }
        }
        if(!valid) break;
        for(auto x : Z[(*it)]){

            hh = x;
            while(hh != node){
                hh=fin(hh);
                if(!need.count(id[hh]) && !has.count(id[hh])){
                    need.insert(id[hh]);
                }
                par[hh] = up[hh];
            }
        }
        has.insert(*it);
        need.erase(it);
    }
    if(valid){
        res = min(res, cur);
    }
    for(auto q : mark){
        now[q]=false;
        par[q]=q;
    }
    ban[node]=true;
    for(auto x : T[node]){
        if(!ban[x])
            decomp(x);
    }
}

int main(){
    fastIO;
    int n, k;
    cin >> n >> k;
    for(int i =1; i <= n; i ++ )
        par[i]=i;
    res = k;
    int u, v;
    for(int i = 1; i < n; i ++ ){
        cin >> u >> v;
        T[u].push_back(v);
        T[v].push_back(u);
    }
    for(int i = 1; i <= n; i ++ ){
        cin >> id[i];
        Z[id[i]].push_back(i);
    }
    decomp(1);
    cout << res - 1;
    return 0;
}

Subtask #1
0 / 1.0

# 결과 실행 시간 메모리 Grader output
1 Execution timed out 3035 ms 9728 KB Time limit exceeded
2 Halted 0 ms 0 KB -

Subtask #2
0 / 10.0

# 결과 실행 시간 메모리 Grader output
1 Execution timed out 3035 ms 9728 KB Time limit exceeded
2 Halted 0 ms 0 KB -

Subtask #3
0 / 30.0

# 결과 실행 시간 메모리 Grader output
1 Execution timed out 3033 ms 39388 KB Time limit exceeded
2 Halted 0 ms 0 KB -

Subtask #4
0 / 59.0

# 결과 실행 시간 메모리 Grader output
1 Execution timed out 3035 ms 9728 KB Time limit exceeded
2 Halted 0 ms 0 KB -