제출 #209578

#	제출 시각	아이디	문제	언어	결과	실행 시간	메모리
209578		nicolaalexandra	Min-max tree (BOI18_minmaxtree)	C++14	0 / 100	1062 ms	46932 KiB

minmaxtree

#include <bits/stdc++.h>
#define DIM 700010
using namespace std;
int level[DIM],fth[DIM];
int E[DIM*4],p[DIM*4],first[DIM],viz[DIM],tata[DIM],dp_min[DIM];
pair <int,int> rmq[30][DIM];
vector <int> L[DIM];
struct _update{
    int tip,x,y,val;
};
_update v[DIM],w[DIM];

int n,m,i,j,x,y,val,dist,lca,k,tip,el;
char ch;

void dfs (int nod, int father){
    E[++k] = nod;
    first[nod] = k;
    level[nod] = 1 + level[father];
    fth[nod] = tata[nod] = father;
    for (int i=0;i<L[nod].size();i++){
        int vecin = L[nod][i];
        if (vecin != father){
            dfs (vecin,nod);
            E[++k] = nod;
        }}}

int get_lca (int x, int y){
    int posx = first[x], posy = first[y];
    if (posx > posy)
        swap (posx,posy);
    int nr = p[posy-posx+1];
    pair <int,int> sol = min (rmq[nr][posx],rmq[nr][posy-(1<<nr)+1]);
    return E[sol.second];
}

inline int cmp (_update a, _update b){
    return a.val < b.val;
}
int main (){

   // ifstream cin ("minmaxtree.in");
   // ofstream cout ("minmaxtree.out");

    cin>>n;
    for (i=1;i<n;i++){
        cin>>x>>y;
        L[x].push_back(y);
        L[y].push_back(x);
    }
    dfs (1,0);

    for (i=1;i<=k;i++)
        rmq[0][i] = make_pair (level[E[i]],i);

    for (i=1;(1<<i)<=k;i++){
        for (j=1;j<=k;j++){
            rmq[i][j] = rmq[i-1][j];
            if (j + (1<<(i-1)) <= k && rmq[i-1][j + (1<<(i-1))].first < rmq[i][j].first)
                rmq[i][j] = rmq[i-1][j + (1<<(i-1))];
        }}

    for (i=2;i<=k;i++)
        p[i] = p[i/2] + 1;

    cin>>m;
    for (i=1;i<=m;i++){
        cin>>ch>>x>>y>>val;
        if (ch == 'M')
            tip = 1;
        else tip = 0;

        v[i] =  {tip,x,y,val};

        if (tip)
            w[++el] = v[i];
    }

    /// dp_min[nod] - minimul valorilor de maxim care trec prin muchia nod-fth[nod]

    sort (w+1,w+el+1,cmp);
    for (i=1;i<=el;i++){
        int x = w[i].x, y = w[i].y, val = w[i].val;
        lca = get_lca (x,y);

        /// acum incerc sa fac toate valorile nemcacate de pe drumul de la x la lca egale cu val
        int nod = x;
        while (level[nod] > level[lca]){

            if (!dp_min[nod]){
                dp_min[nod] = val;

                for (auto vecin : L[nod]){
                    if (vecin != tata[nod])
                        fth[vecin] = lca;
                }
            }

            nod = fth[nod];
        }


        nod = y;
        while (level[nod] > level[lca]){

            if (!dp_min[nod]){
                dp_min[nod] = val;

                for (auto vecin : L[nod]){
                    if (vecin != tata[nod])
                        fth[vecin] = lca;
                }
            }

            nod = fth[nod];
        }
    }

    for (i=2;i<=n;i++)
        cout<<i<<" "<<tata[i]<<" "<<dp_min[i]<<"\n";


    return 0;
}

컴파일 시 표준 에러 (stderr) 메시지

minmaxtree.cpp: In function 'void dfs(int, int)':
minmaxtree.cpp:21:19: warning: comparison between signed and unsigned integer expressions [-Wsign-compare]
     for (int i=0;i<L[nod].size();i++){
                  ~^~~~~~~~~~~~~~

• Subtask 1: 0 / 7
• Subtask 2: 0 / 22
• Subtask 3: 0 / 29
• Subtask 4: 0 / 42