Submission #64367

#	Time	Username	Problem	Language	Result	Execution time	Memory
64367		theknife2001	Dreaming (IOI13_dreaming)	C++17	0 / 100	131 ms	10744 KiB

dreaming

#include <bits/stdc++.h>
#include "dreaming.h"
#define ii pair< int , int >
#define se second
#define fi first

using namespace std;
const int N=1e5+55;
vector < ii > vec[N];
bool visited[N];
int d=0;
int md=0;
int l=1e9+5000;
int node;

int dfs(int u , int p ,bool q)
{
//    cout<<u<<' '<<p<<endl;
    visited[u]=1;
    int d1=0,d2=0;
    int v,c;
    int temp=0;
    for(auto x:vec[u])
    {
        v=x.fi;
        c=x.se;
        if(v==p)
            continue;
        temp=dfs(v,u,q);
        temp+=c;
        if(temp>d2)
            d2=temp;
        if(d2>d1)
            swap(d1,d2);
    }
    if(!q&&d<d1+d2)
        d=d1+d2;
    if(q)
    {
        if(l>max(d1,d-d1))
        {
            l=max(d1,d-d1);
            node=u;
        }
    }
    return d1;
}

int travelTime(int n, int M, int L, int A[], int B[], int T[])
{
    for(int i=0;i<M;i++)
    {
        vec[B[i]].push_back({A[i],T[i]});
        vec[A[i]].push_back({B[i],T[i]});
    }
    vector < ii > ln;
    memset(visited,0,sizeof visited);
    for(int i=0;i<n;i++)
    {
        if(visited[i]==0)
        {
            d=0;
            dfs(i,i,0);
            l=1e9+5555;
            dfs(i,i,1);
            md=max(md,d);
            if(l==0)
                node=i;
            ln.push_back({l,node});
        }
    }
    sort(ln.begin(),ln.end());
    int s=ln.size();
    if(s==1)
        return ln[0].fi;
    for(int i=0;i<s-1;i++)
    {
        vec[ln[i].se].push_back({ln[s-1].se,L});
        vec[ln[s-1].se].push_back({ln[i].se,L});
    }
    dfs(0,-1,0);
    return md;
}

• Subtask 1: 0 / 14
• Subtask 2: 0 / 10
• Subtask 3: 0 / 23
• Subtask 4: 0 / 18
• Subtask 5: 0 / 12
• Subtask 6: 0 / 23