2025/3/15

#include<iostream>

#include<vector>

using namespace std;

int n;

vector <int>a[1555];

bool head[1555];

int self[1555],kids[1555];

void dp(int fa,int u)

{

for(int i=0;i<a[u].size();i++)

{

int v=a[u][i];

if(v==fa)continue;

dp(u,v);

kids[u]+=self[v];

self[u]+=min(self[v],kids[v]);

}

}

int main()

{

cin>>n;

for(int i=1;i<=n;i++)

{

int x,m;

cin>>x>>m;

for(int j=1;j<=m;j++)

{

int y;

cin>>y;

a[x].push_back(y); 

a[y].push_back(x);

}

}

for(int i=0;i<=n-1;i++)self[i]=1;

dp(-1,0);

cout<<min(self[0],kids[0]);

// for(int j=0;j<=n-1;j++)cout<<self[j]<<" "<<kids[j]<<"\n"; 

// for(int i=0;i<=n-1;i++)

// {

// for(int j=0;j<a[i].size();j++)

// cout<<a[i][j]<<" ";

// cout<<"\n";

// }

return 0;

}

 

 

 

 

#include<iostream>

using namespace std;

int n,head[10010],tot=0;

struct EDGE

{

int to,next,weight;

}edge[10010];

void add(int a,int b,int c)

{

edge[++tot].weight=c;

edge[tot].to=b;

edge[tot].next=head[a];

head[a]=tot;

}

int longest[10010],longer[10010],falong[10010],inlong[10010];

int dfs(int u,int fa) 

{

if(longest[u]>0) return longest[u];

for(int i=head[u];i;i=edge[i].next)

{

int v=edge[i].to;

if(v==fa)continue;

if(longest[u]<dfs(v,u)+edge[i].weight)

{

inlong[u]=v;

longer[u]=longest[u];

longest[u]=dfs(v,u)+edge[i].weight;

}

else if(longer[u]<dfs(v,u)+edge[i].weight)

longer[u]=dfs(v,u)+edge[i].weight;

}

return longest[u];

}

void dfs2(int u,int fa)

{

for(int i=head[u];i;i=edge[i].next)

{

int v=edge[i].to;

if(v==fa)continue;

if(inlong[u]==v)falong[v]=max(falong[u],longer[u])+edge[i].weight;

else falong[v]=max(falong[u],longest[u])+edge[i].weight;

dfs2(v,u);

// cout<<u<<" "<<fa<<" "<<v<<" "<<falong[v]<<"\n";

}

}

int main()

{

cin>>n;

for(int i=2;i<=n;i++)

{

int y,w;

cin>>y>>w;

add(i,y,w);

add(y,i,w);

}

dfs(1,-1);

dfs2(1,-1);

for(int i=1;i<=n;i++)cout<<max(longest[i],falong[i])<<"\n";

// for(int i=1;i<=n;i++)cout<<longest[i]<<" "<<longer[i]<<" "<<falong[i]<<" "<<inlong[i]<<"\n";

return 0;

}

 

 

 

 

 

 

 

#include<iostream>
#include<cstring>
using namespace std;
string c;
int main()
{
    cin>>c;
    for(int i=0;i<c.length();i++)if(int(c[i])>90)c[i]=char(c[i]-32);
    char ch=c[0];
    int cnt=0;
    for(int i=0;i<c.length();i++)
        if(ch==c[i])cnt++;
        else
        {
            cout<<"("<<c[i-1]<<","<<cnt<<")";
            cnt=1;
            ch=c[i];
        }
    cout<<"("<<c[c.length()-1]<<","<<cnt<<")";
    return 0;
}