제출 #1272288

#	제출 시각	아이디	문제	언어	결과	실행 시간	메모리
1272288		trandangquang	수도 (JOI20_capital_city)	C++20	0 / 100	315 ms	36736 KiB

capital_city

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

#define foru(i,a,b) for(int i=(a); i<=(b); ++i)
#define ford(i,a,b) for(int i=(a); i>=(b); --i)
#define rep(i,a) for(int i=0; i<(a); ++i)
#define sz(a) (int)(a).size()
#define all(a) (a).begin(),(a).end()
#define bit(s,i) (((s)>>(i))&1)
#define ii pair<int,int>
#define fi first
#define se second
#define pb push_back
#define eb emplace_back
#define ll long long

template <class X, class Y> bool maxi(X &x, Y y){return x<y?x=y,true:false;}
template <class X, class Y> bool mini(X &x, Y y){return x>y?x=y,true:false;}

const int N=2e5+5;

int n,k,cntTot[N],col[N],ans=1e9;
vector<int> adj[N];

int sz[N]; bool del[N];

void get_sz(int u, int p){
    sz[u]=1;
    for(int v:adj[u]) if(!del[v] && v!=p){
        get_sz(v,u);
        sz[u]+=sz[v];
    }
}

int centroid(int u, int p, int szA){
    for(int v:adj[u]) if(!del[v] && v!=p){
        if(sz[v]>szA/2) return centroid(v,u,szA);
    }
    return u;
}

int par[N]; bool visCol[N];
vector<int> lst[N],lstCol;

void dfs(int u, int p){
    lst[col[u]].eb(u);
    lstCol.eb(col[u]);
    par[u]=p;

    for(int v:adj[u]) if(!del[v] && v!=p){
        dfs(v,u);
    }
}

void decomp(int u){
    get_sz(u,-1);
    int cen=centroid(u,-1,sz[u]);
    dfs(cen,-1);

    vector<int> hi;
    hi=lst[col[u]];

    if(sz(hi) == cntTot[col[u]]){
        bool chk=1;

        int cnt=0;

        visCol[col[u]]=true;
        while(hi.size()){
            int p=par[hi.back()]; hi.pop_back();
            if(p!=-1){
                if(!visCol[col[p]]){
                    visCol[col[p]]=1; ++cnt;
                    if(sz(lst[col[p]]) < cntTot[col[p]]){
                        chk=0;
                        break;
                    }
                    for(int i:lst[col[p]]){
                        hi.eb(i);
                    }
                }
            }
        }

        if(chk) mini(ans, cnt);
    }

    for(int i:lstCol){
        lst[i].clear();
        visCol[i]=0;
    }
    lstCol.clear();

    del[cen]=true;
    for(int v:adj[cen]) if(!del[v]) decomp(v);
}

void solve(){
    cin>>n>>k;
    rep(i,n-1){
        int u,v; cin>>u>>v;
        adj[u].eb(v); adj[v].eb(u);
    }
    foru(i,1,n) cin>>col[i], cntTot[col[i]]++;

    decomp(1);
    cout<<ans<<'\n';
}

int32_t main(){
    #define task "test"
    if(fopen(task".inp","r")){
        freopen(task".inp","r",stdin);
        freopen(task".out","w",stdout);
    }
    cin.tie(0)->sync_with_stdio(0);

    int tc=1; //cin>>tc;
    rep(_,tc){
        solve();
    }
}

컴파일 시 표준 에러 (stderr) 메시지

capital_city.cpp: In function 'int32_t main()':
capital_city.cpp:113:16: warning: ignoring return value of 'FILE* freopen(const char*, const char*, FILE*)' declared with attribute 'warn_unused_result' [-Wunused-result]
  113 |         freopen(task".inp","r",stdin);
      |         ~~~~~~~^~~~~~~~~~~~~~~~~~~~~~
capital_city.cpp:114:16: warning: ignoring return value of 'FILE* freopen(const char*, const char*, FILE*)' declared with attribute 'warn_unused_result' [-Wunused-result]
  114 |         freopen(task".out","w",stdout);
      |         ~~~~~~~^~~~~~~~~~~~~~~~~~~~~~~

• Subtask 1: 0 / 1
• Subtask 2: 0 / 10
• Subtask 3: 0 / 30
• Subtask 4: 0 / 59