oj.uz

Submission #1039542

# Submission time Handle Problem Language Result Execution time Memory
1039542 2024-07-31T04:06:40 Z DucNguyen2007 Mergers (JOI19_mergers) C++14
0 / 100
 83 ms 58128 KB 
#include<bits/stdc++.h>
using namespace std;
#define ll long long
#define ld long double
#define pii pair<int,int>
#define pll pair<ll,ll>
#define fi first
#define se second
const int maxN=5e5+5,LG=__lg(maxN)+5;
const ll inf=2e18;
int n,k,a[maxN+1],num[maxN+1],timer=0,h[maxN+1],up[maxN+1][LG+1],f[maxN+1];
vector<int> adj[maxN+1],vec[maxN+1],nadj[maxN+1];
void dfs(int u)
{
    num[u]=++timer;
    for(auto v:adj[u])
    {
        if(v==up[u][0])
        {
            continue;
        }
        up[v][0]=u;
        h[v]=h[u]+1;
        for(int j=1;j<=LG;j++)
        {
            up[v][j]=up[up[v][j-1]][j-1];
        }
        dfs(v);
    }
}
int lca(int u,int v)
{
    if(h[u]<h[v])
    {
        swap(u,v);
    }
    for(int j=LG;j>=0;j--)
    {
        if(h[up[u][j]]>=up[v][j])
        {
            u=up[u][j];
        }
    }
    if(u==v)
    {
        return u;
    }
    for(int j=LG;j>=0;j--)
    {
        if(up[u][j]!=up[v][j])
        {
            u=up[u][j];
            v=up[v][j];
        }
    }
    return up[u][0];
}
void dfs1(int u)
{
    for(auto v:adj[u])
    {
        if(v!=up[u][0])
        {
            dfs1(v);
            f[u]+=f[v];
        }
    }
}
void dfs2(int u,int p)
{
    for(auto v:adj[u])
    {
        if(v!=up[u][0])
        {
            int nv=p;
            if(!f[v])
            {
                //cout<<u<<" "<<v<<'\n';
                nadj[v].push_back(p);
                nadj[p].push_back(v);
                nv=v;
            }
            dfs2(v,nv);
        }
    }
}
int main()
{
    //freopen("","r",stdin);
    //freopen("","w",stdout);
    ios_base::sync_with_stdio(0);
    cin.tie(0);
    cout.tie(0);
    cin>>n>>k;
    for(int i=1;i<n;i++)
    {
        int u,v;
        cin>>u>>v;
        adj[u].push_back(v);
        adj[v].push_back(u);
    }
    h[1]=1;
    dfs(1);
    for(int i=1;i<=n;i++)
    {
        cin>>a[i];
        vec[a[i]].push_back(i);
    }
    for(int i=1;i<=k;i++)
    {
        sort(vec[i].begin(),vec[i].end(),[&](int x,int y)
        {
            return num[x]<num[y];
        });
        int len=vec[i].size();
        if(len==1)
        {
            continue;
        }
        for(int j=0;j<len;j++)
        {
            int u=vec[i][j],v=vec[i][(j+1)%len];
            f[u]++;
            f[lca(u,v)]--;
        }
    }
    dfs1(1);
    dfs2(1,1);
    int cnt=0;
    for(int i=1;i<=n;i++)
    {
        cnt+=(nadj[i].size()==1);
    }
    cout<<(cnt+1)/2;
}

Subtask #1
0 / 10.0

# Verdict Execution time Memory Grader output
1 Correct 15 ms 35676 KB Output is correct
2 Incorrect 15 ms 35676 KB Output isn't correct
3 Halted 0 ms 0 KB -

Subtask #2
0 / 24.0

# Verdict Execution time Memory Grader output
1 Correct 15 ms 35676 KB Output is correct
2 Incorrect 15 ms 35676 KB Output isn't correct
3 Halted 0 ms 0 KB -

Subtask #3
0 / 14.0

# Verdict Execution time Memory Grader output
1 Correct 15 ms 35676 KB Output is correct
2 Incorrect 15 ms 35676 KB Output isn't correct
3 Halted 0 ms 0 KB -

Subtask #4
0 / 22.0

# Verdict Execution time Memory Grader output
1 Correct 83 ms 52204 KB Output is correct
2 Correct 81 ms 58128 KB Output is correct
3 Incorrect 18 ms 36212 KB Output isn't correct
4 Halted 0 ms 0 KB -

Subtask #5
0 / 30.0

# Verdict Execution time Memory Grader output
1 Correct 15 ms 35676 KB Output is correct
2 Incorrect 15 ms 35676 KB Output isn't correct
3 Halted 0 ms 0 KB -