Submission #130524

#	Time	Username	Problem	Language	Result	Execution time	Memory
130524		Bodo171	Mergers (JOI19_mergers)	C++14	100 / 100	2195 ms	190164 KiB

mergers

#include <iostream>
#include <fstream>
#include <map>
#include <vector>
using namespace std;
const int nmax=500005;
map<int,int> ap[nmax];
vector<int> v[nmax];
int l[nmax],r[nmax],p[nmax],closed[nmax],w[nmax],sons[nmax],rele[nmax],tot[nmax],col[nmax],c[nmax],tt[nmax];
int nr,n,i,paths,k,x,y,frz;
void baga(int path,int cc)
{
    ap[path][cc]++;
    if(ap[path][cc]==1) rele[path]++;
    if(ap[path][cc]==tot[cc]) rele[path]--;
}
void dfs(int x)
{
    int big=0;
    w[x]=1;
    ++nr;l[x]=nr;col[nr]=c[x];
    for(int i=0;i<v[x].size();i++)
        if(!w[v[x][i]])
    {
        tt[v[x][i]]=x;
        dfs(v[x][i]);
        if(w[v[x][i]]>w[big])
            big=v[x][i];
        w[x]+=w[v[x][i]];
    }
    if(big&&(!closed[big])) p[x]=p[big];
    else
    {
        p[x]=++paths;
        if(big) sons[paths]++;
    }
    baga(p[x],c[x]);
    for(int i=0;i<v[x].size();i++)
        if(v[x][i]!=big&&v[x][i]!=tt[x])
    {
        if(closed[v[x][i]]) sons[p[x]]++;
        else
        {
            sons[p[x]]+=sons[p[v[x][i]]];
            for(int j=l[v[x][i]];j<=r[v[x][i]];j++)
                baga(p[x],col[j]);
        }
    }
    if(rele[p[x]]==0)
    {
        closed[x]=1;
        if(sons[p[x]]==0) frz++;
    }
    r[x]=nr;
}
int main()
{
    //freopen("data.in","r",stdin);
    ios_base::sync_with_stdio(false);
    cin>>n>>k;
    for(i=1;i<=n-1;i++)
    {
        cin>>x>>y;
        v[x].push_back(y);
        v[y].push_back(x);
    }
    for(i=1;i<=n;i++)
    {
        cin>>c[i];
        tot[c[i]]++;
    }
    dfs(1);
    if(sons[p[1]]==1) frz++;
    if(frz==1) frz=0;
    cout<<(frz+1)/2;
    return 0;
}

Compilation message (stderr)

mergers.cpp: In function 'void dfs(int)':
mergers.cpp:22:18: warning: comparison between signed and unsigned integer expressions [-Wsign-compare]
     for(int i=0;i<v[x].size();i++)
                 ~^~~~~~~~~~~~
mergers.cpp:38:18: warning: comparison between signed and unsigned integer expressions [-Wsign-compare]
     for(int i=0;i<v[x].size();i++)
                 ~^~~~~~~~~~~~

• Subtask 1: 10 / 10
• Subtask 2: 24 / 24
• Subtask 3: 14 / 14
• Subtask 4: 22 / 22
• Subtask 5: 30 / 30