Submission #923335

#	Time	Username	Problem	Language	Result	Execution time	Memory
923335		abcvuitunggio	Beech Tree (IOI23_beechtree)	C++17	0 / 100	2063 ms	44432 KiB

beechtree

#include "beechtree.h"
#include <bits/stdc++.h>
using namespace std;
int n,m,bad[200001],cnt[200001],sz[200001],pos[200001],id,p[200001][20],d[200001],ch[200001];
vector <int> par,c,res,T[200001],ke[200001],ve[200001];
void dfs(int u){
    sz[u]=1;
    for (int v:ke[u]){
        dfs(v);
        sz[u]+=sz[v];
    }
    ve[sz[u]].push_back(u);
}
void dfs2(int u){
    T[u].push_back(u);
    for (int v:ke[u]){
        dfs2(v);
        for (int i:T[v])
            T[u].push_back(i);
    }
    sort(T[u].begin(),T[u].end(),[](int i, int j){return pos[i]<pos[j];});
    for (int i=1;i<T[u].size()&&!bad[u];i++)
        for (int j=i+1;j<T[u].size()&&!bad[u];j++){
            int x=T[u][i],y=T[u][j];
            if (c[x]==c[y]&&pos[par[x]]>pos[par[y]])
                bad[u]=1;
            if (ke[x].size()<ke[y].size())
                bad[u]=1;
        }
}
void dfs3(int u){
    for (int v:ke[u]){
        dfs3(v);
        bad[u]|=bad[v];
    }
}
int lca(int u, int v){
    u++,v++;
    if (d[u]<d[v])
        swap(u,v);
    int x=d[u]-d[v];
    for (int i=0;i<20;i++)
        if ((x>>i)&1)
            u=p[u][i];
    if (u==v)
        return u-1;
    for (int i=19;i>=0;i--)
        if (p[u][i]!=p[v][i]){
            u=p[u][i];
            v=p[v][i];
        }
    return p[u][0]-1;
}
vector <int> beechtree(int N, int M, vector<int> P, vector<int> C){
    n=N,m=M,par=P,c=C;
    for (int i=1;i<n;i++)
        ke[P[i]].push_back(i);
    for (int i=0;i<n;i++){
        sort(ke[i].begin(),ke[i].end(),[](int i, int j){return make_pair(c[i],i)<make_pair(c[j],j);});
        for (int j=1;j<ke[i].size();j++)
            if (c[ke[i][j]]==c[ke[i][j-1]])
                bad[i]=1;
        p[i+1][0]=P[i]+1;
        d[i+1]=d[P[i]+1]+1;
        for (int j=1;j<20;j++)
            p[i+1][j]=p[p[i+1][j-1]][j-1];
    }
    for (int i=n-1;i>=0;i--)
        for (int j=n-1;j>i;j--){
            int u=i,v=j;
            if (ke[i].size()>ke[j].size())
                swap(u,v);
            for (int k:ke[u])
                ch[c[k]]=1;
            int cnt=0;
            for (int k:ke[v])
                cnt+=ch[c[k]];
            for (int k:ke[u])
                ch[c[k]]=0;
            if (cnt!=ke[u].size()){
                bad[lca(i,j)]=1;
                continue;
            }
        }
    dfs(0);
    for (int i=n;i>=0;i--){
        sort(ve[i].begin(),ve[i].end(),[](int u, int v){return pos[par[u]]<pos[par[v]];});
        for (int j:ve[i])
            pos[j]=++id;
    }
    dfs2(0);
    dfs3(0);
    for (int i=0;i<n;i++)
        res.push_back(bad[i]^1);
    return res;
}

Compilation message (stderr)

beechtree.cpp: In function 'void dfs2(int)':
beechtree.cpp:22:19: warning: comparison of integer expressions of different signedness: 'int' and 'std::vector<int>::size_type' {aka 'long unsigned int'} [-Wsign-compare]
   22 |     for (int i=1;i<T[u].size()&&!bad[u];i++)
      |                  ~^~~~~~~~~~~~
beechtree.cpp:23:25: warning: comparison of integer expressions of different signedness: 'int' and 'std::vector<int>::size_type' {aka 'long unsigned int'} [-Wsign-compare]
   23 |         for (int j=i+1;j<T[u].size()&&!bad[u];j++){
      |                        ~^~~~~~~~~~~~
beechtree.cpp: In function 'std::vector<int> beechtree(int, int, std::vector<int>, std::vector<int>)':
beechtree.cpp:60:23: warning: comparison of integer expressions of different signedness: 'int' and 'std::vector<int>::size_type' {aka 'long unsigned int'} [-Wsign-compare]
   60 |         for (int j=1;j<ke[i].size();j++)
      |                      ~^~~~~~~~~~~~~
beechtree.cpp:80:20: warning: comparison of integer expressions of different signedness: 'int' and 'std::vector<int>::size_type' {aka 'long unsigned int'} [-Wsign-compare]
   80 |             if (cnt!=ke[u].size()){
      |                 ~~~^~~~~~~~~~~~~~

• Subtask 0: 0 / 0
• Subtask 1: 0 / 9
• Subtask 2: 0 / 5
• Subtask 3: 0 / 9
• Subtask 4: 0 / 8
• Subtask 5: 0 / 14
• Subtask 6: 0 / 14
• Subtask 7: 0 / 12
• Subtask 8: 0 / 17
• Subtask 9: 0 / 12