oj.uz

Submission #223906

# Submission time Handle Problem Language Result Execution time Memory
223906 2020-04-16T20:31:10 Z medk Capital City (JOI20_capital_city) C++14
11 / 100
 3000 ms 66920 KB 
#include <bits/stdc++.h>

#define ll long long
#define pb push_back
#define x first
#define y second
#define all(u) u.begin(),u.end()
#define sz(u) (int)(u.size())
#define INF (int)(1e9)

using namespace std;

const int MAXN=2e5+5;

int n,k,ans=INF;
vector<vector<int>> tr(MAXN),grp(MAXN),cd(MAXN);
int col[MAXN],subsz[MAXN],parcd[MAXN],par[MAXN],dpth[MAXN],in[MAXN],dpthcd[MAXN];
bool blocked[MAXN];
vector<vector<int>> lca(MAXN,vector<int>(20));
int root=-1;
vector<int> eul;

void calc_sz(int u, int pr)
{
    subsz[u]=1;
    for(int v:tr[u])
    {
        if(v==pr || blocked[v]) continue;
        calc_sz(v,u);
        subsz[u]+=subsz[v];
    }
}

int find_centroid(int u, int pr, int tar)
{
    for(int v:tr[u])
    {
        if(v==pr || blocked[v]) continue;
        if(subsz[v]>tar) return find_centroid(v,u,tar);
    }
    return u;
}

void decomp(int u, int pr, int d=0)
{
    memset(subsz,0,sizeof(subsz));
    calc_sz(u,pr);
    int centroid=find_centroid(u,pr,subsz[u]/2);
    blocked[centroid]=1;
    parcd[centroid]=pr;
    dpthcd[centroid]=d;
    if(pr==-1) root=centroid;
    else
    {
        cd[centroid].pb(pr);
        cd[pr].pb(centroid);
    }
    for(int v:tr[centroid])
    {
        if(blocked[v]) continue;
        decomp(v,centroid,d+1);
    }
}

void makeul(int u, int pr, int d)
{
    in[u]=sz(eul);
    eul.pb(u);
    dpth[u]=d;
    par[u]=pr;
    d++;
    for(int v:tr[u])
    {
        if(pr==v) continue;
        makeul(v,u,d);
        eul.pb(u);
    }
}

int getlca(int u, int v)
{
    int l=in[u], r=in[v];
    if(l>r) swap(l,r);
    int lg=log2(r-l+1);
    if(dpth[lca[l][lg]]<=dpth[lca[r-(1<<lg)+1][lg]]) return lca[l][lg];
    return lca[r-(1<<lg)+1][lg];
}

int lcacd(int u, int v)
{
    if(dpthcd[u]==dpthcd[v])
    {
        if(u==v) return u;
        else return lcacd(parcd[u],parcd[v]);
    }
    if(dpthcd[v]<dpthcd[u]) swap(u,v);
    return lcacd(u,parcd[v]);
}

void solve(int rt, int pr)
{
    unordered_map<int,int> visver;
    unordered_map<int,int> rep;
    int lc=rt, used=0;
    queue<int> q;
    q.push(rt);
    visver[rt]=1;
    rep[col[rt]]=rt;
    bool bug=0;
    while(!q.empty())
    {
        int u=q.front(); q.pop();
        visver[u]=2;
        if(u!=lc)
        {
            int mypar=par[u];
            if(visver[mypar]==0 && col[mypar]!=col[u] && !rep.count(col[mypar]))
            {
                if(lcacd(mypar,rt)!=rt)
                {
                    bug=1;
                    break;
                }
                q.push(mypar);
                visver[mypar]=1;
                rep[col[mypar]]=mypar;
            }
        }
        if(rep[col[u]]!=u) continue;
        used++;
        for(int v:grp[col[u]])
        {
            if(v==u) continue;
            int newlc=getlca(lc,v);
            if(newlc!=lc)
            {
                if(visver[lc]==2)
                {
                    if(lcacd(par[lc],rt)!=rt)
                    {
                        bug=1;
                        break;
                    }
                    if(!rep.count(col[par[lc]]))
                    {
                        q.push(par[lc]);
                        visver[par[lc]]=1;
                        rep[col[par[lc]]]=par[lc];
                    }
                }
                lc=newlc;
            }
            if(lcacd(v,rt)!=rt)
            {
                bug=1;
                break;
            }
            visver[v]=1;
            q.push(v);
        }
        if(bug) break;
    }
    if(!bug) ans=min(ans,used);
    for(int v:cd[rt])
    {
        if(v==pr) continue;
        solve(v,rt);
    }
}

int main()
{
    //freopen("test.in","r",stdin);
    ios::sync_with_stdio(0); cin.tie(0); cout.tie(0);
    cin>>n>>k;
    for(int i=0;i<n-1;i++)
    {
        int u,v; cin>>u>>v;
        u--,v--;
        tr[u].pb(v);
        tr[v].pb(u);
    }
    for(int i=0;i<n;i++)
    {
        cin>>col[i];
        col[i]--;
        grp[col[i]].pb(i);
    }
    decomp(0,-1);
    makeul(0,-1,0);
    for(int i=0;i<sz(eul);i++) lca[i][0]=eul[i];
    for(int j=1;j<20;j++)
        for(int i=0;i+(1<<j)<=sz(eul);i++)
            lca[i][j]=(dpth[lca[i][j-1]]<=dpth[lca[i+(1<<(j-1))][j-1]]?lca[i][j-1]:lca[i+(1<<(j-1))][j-1]);
    solve(root,-1);
    cout<<ans-1<<'\n';
}

Subtask #1
1.0 / 1.0

# Verdict Execution time Memory Grader output
1 Correct 32 ms 38784 KB Output is correct
2 Correct 31 ms 38784 KB Output is correct
3 Correct 31 ms 38784 KB Output is correct
4 Correct 31 ms 38776 KB Output is correct
5 Correct 30 ms 38784 KB Output is correct
6 Correct 31 ms 38776 KB Output is correct
7 Correct 32 ms 38784 KB Output is correct
8 Correct 31 ms 38776 KB Output is correct
9 Correct 31 ms 38784 KB Output is correct
10 Correct 31 ms 38784 KB Output is correct

Subtask #2
10.0 / 10.0

# Verdict Execution time Memory Grader output
1 Correct 32 ms 38784 KB Output is correct
2 Correct 31 ms 38784 KB Output is correct
3 Correct 31 ms 38784 KB Output is correct
4 Correct 31 ms 38776 KB Output is correct
5 Correct 30 ms 38784 KB Output is correct
6 Correct 31 ms 38776 KB Output is correct
7 Correct 32 ms 38784 KB Output is correct
8 Correct 31 ms 38776 KB Output is correct
9 Correct 31 ms 38784 KB Output is correct
10 Correct 31 ms 38784 KB Output is correct
11 Correct 79 ms 39032 KB Output is correct
12 Correct 83 ms 39036 KB Output is correct
13 Correct 80 ms 39032 KB Output is correct
14 Correct 78 ms 39032 KB Output is correct
15 Correct 82 ms 39032 KB Output is correct
16 Correct 80 ms 39032 KB Output is correct
17 Correct 78 ms 39104 KB Output is correct
18 Correct 86 ms 39032 KB Output is correct
19 Correct 80 ms 39032 KB Output is correct
20 Correct 87 ms 39160 KB Output is correct
21 Correct 78 ms 39032 KB Output is correct
22 Correct 81 ms 39032 KB Output is correct
23 Correct 80 ms 39032 KB Output is correct
24 Correct 84 ms 39088 KB Output is correct
25 Correct 86 ms 39112 KB Output is correct
26 Correct 87 ms 39160 KB Output is correct
27 Correct 80 ms 39160 KB Output is correct
28 Correct 79 ms 39032 KB Output is correct
29 Correct 80 ms 39032 KB Output is correct
30 Correct 81 ms 39160 KB Output is correct

Subtask #3
0 / 30.0

# Verdict Execution time Memory Grader output
1 Execution timed out 3079 ms 66920 KB Time limit exceeded
2 Halted 0 ms 0 KB -

Subtask #4
0 / 59.0

# Verdict Execution time Memory Grader output
1 Correct 32 ms 38784 KB Output is correct
2 Correct 31 ms 38784 KB Output is correct
3 Correct 31 ms 38784 KB Output is correct
4 Correct 31 ms 38776 KB Output is correct
5 Correct 30 ms 38784 KB Output is correct
6 Correct 31 ms 38776 KB Output is correct
7 Correct 32 ms 38784 KB Output is correct
8 Correct 31 ms 38776 KB Output is correct
9 Correct 31 ms 38784 KB Output is correct
10 Correct 31 ms 38784 KB Output is correct
11 Correct 79 ms 39032 KB Output is correct
12 Correct 83 ms 39036 KB Output is correct
13 Correct 80 ms 39032 KB Output is correct
14 Correct 78 ms 39032 KB Output is correct
15 Correct 82 ms 39032 KB Output is correct
16 Correct 80 ms 39032 KB Output is correct
17 Correct 78 ms 39104 KB Output is correct
18 Correct 86 ms 39032 KB Output is correct
19 Correct 80 ms 39032 KB Output is correct
20 Correct 87 ms 39160 KB Output is correct
21 Correct 78 ms 39032 KB Output is correct
22 Correct 81 ms 39032 KB Output is correct
23 Correct 80 ms 39032 KB Output is correct
24 Correct 84 ms 39088 KB Output is correct
25 Correct 86 ms 39112 KB Output is correct
26 Correct 87 ms 39160 KB Output is correct
27 Correct 80 ms 39160 KB Output is correct
28 Correct 79 ms 39032 KB Output is correct
29 Correct 80 ms 39032 KB Output is correct
30 Correct 81 ms 39160 KB Output is correct
31 Execution timed out 3079 ms 66920 KB Time limit exceeded
32 Halted 0 ms 0 KB -