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Submission #223904

# Submission time Handle Problem Language Result Execution time Memory
223904 2020-04-16T20:27:34 Z medk Capital City (JOI20_capital_city) C++14
11 / 100
 458 ms 132112 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];
int lca[MAXN][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)
{
    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 12 ms 14464 KB Output is correct
2 Correct 12 ms 14464 KB Output is correct
3 Correct 12 ms 14464 KB Output is correct
4 Correct 12 ms 14464 KB Output is correct
5 Correct 12 ms 14464 KB Output is correct
6 Correct 12 ms 14464 KB Output is correct
7 Correct 12 ms 14464 KB Output is correct
8 Correct 12 ms 14464 KB Output is correct
9 Correct 12 ms 14464 KB Output is correct
10 Correct 12 ms 14464 KB Output is correct

Subtask #2
10.0 / 10.0

# Verdict Execution time Memory Grader output
1 Correct 12 ms 14464 KB Output is correct
2 Correct 12 ms 14464 KB Output is correct
3 Correct 12 ms 14464 KB Output is correct
4 Correct 12 ms 14464 KB Output is correct
5 Correct 12 ms 14464 KB Output is correct
6 Correct 12 ms 14464 KB Output is correct
7 Correct 12 ms 14464 KB Output is correct
8 Correct 12 ms 14464 KB Output is correct
9 Correct 12 ms 14464 KB Output is correct
10 Correct 12 ms 14464 KB Output is correct
11 Correct 15 ms 15104 KB Output is correct
12 Correct 15 ms 15104 KB Output is correct
13 Correct 15 ms 15104 KB Output is correct
14 Correct 15 ms 15104 KB Output is correct
15 Correct 15 ms 15104 KB Output is correct
16 Correct 15 ms 15104 KB Output is correct
17 Correct 16 ms 15104 KB Output is correct
18 Correct 14 ms 15104 KB Output is correct
19 Correct 15 ms 15104 KB Output is correct
20 Correct 20 ms 15104 KB Output is correct
21 Correct 15 ms 15104 KB Output is correct
22 Correct 15 ms 15104 KB Output is correct
23 Correct 16 ms 15104 KB Output is correct
24 Correct 17 ms 15360 KB Output is correct
25 Correct 16 ms 15232 KB Output is correct
26 Correct 16 ms 15232 KB Output is correct
27 Correct 15 ms 15232 KB Output is correct
28 Correct 15 ms 15104 KB Output is correct
29 Correct 15 ms 15088 KB Output is correct
30 Correct 15 ms 15104 KB Output is correct

Subtask #3
0 / 30.0

# Verdict Execution time Memory Grader output
1 Runtime error 458 ms 132112 KB Execution killed with signal 11 (could be triggered by violating memory limits)
2 Halted 0 ms 0 KB -

Subtask #4
0 / 59.0

# Verdict Execution time Memory Grader output
1 Correct 12 ms 14464 KB Output is correct
2 Correct 12 ms 14464 KB Output is correct
3 Correct 12 ms 14464 KB Output is correct
4 Correct 12 ms 14464 KB Output is correct
5 Correct 12 ms 14464 KB Output is correct
6 Correct 12 ms 14464 KB Output is correct
7 Correct 12 ms 14464 KB Output is correct
8 Correct 12 ms 14464 KB Output is correct
9 Correct 12 ms 14464 KB Output is correct
10 Correct 12 ms 14464 KB Output is correct
11 Correct 15 ms 15104 KB Output is correct
12 Correct 15 ms 15104 KB Output is correct
13 Correct 15 ms 15104 KB Output is correct
14 Correct 15 ms 15104 KB Output is correct
15 Correct 15 ms 15104 KB Output is correct
16 Correct 15 ms 15104 KB Output is correct
17 Correct 16 ms 15104 KB Output is correct
18 Correct 14 ms 15104 KB Output is correct
19 Correct 15 ms 15104 KB Output is correct
20 Correct 20 ms 15104 KB Output is correct
21 Correct 15 ms 15104 KB Output is correct
22 Correct 15 ms 15104 KB Output is correct
23 Correct 16 ms 15104 KB Output is correct
24 Correct 17 ms 15360 KB Output is correct
25 Correct 16 ms 15232 KB Output is correct
26 Correct 16 ms 15232 KB Output is correct
27 Correct 15 ms 15232 KB Output is correct
28 Correct 15 ms 15104 KB Output is correct
29 Correct 15 ms 15088 KB Output is correct
30 Correct 15 ms 15104 KB Output is correct
31 Runtime error 458 ms 132112 KB Execution killed with signal 11 (could be triggered by violating memory limits)
32 Halted 0 ms 0 KB -