Submission #915565

#	Time	Username	Problem	Language	Result	Execution time	Memory
915565		AndrijaM	Valley (BOI19_valley)	C++14	0 / 100	162 ms	15976 KiB

valley

#include <bits/stdc++.h>
using namespace std;

const long long maxn=1e5+10;
const long long logn=25;
const long long mod=1e9+7;

int n,s,q,e;
vector<pair<int,int>>g[maxn];
set<int>ins;
vector<pair<int,int>>pr;

struct node
{
    int idx;
    int dis;
    node(){}
    node(int _idx,int _dis)
    {
        idx=_idx;
        dis=_dis;
    }
    bool operator <(const node &tmp)const
    {
        return dis>tmp.dis;
    }
};

int main()
{
    cin>>n>>s>>q>>e;
    for(int i=0;i<n-1;i++)
    {
        int a,b,c;
        cin>>a>>b>>c;
        a--;b--;
        g[a].push_back({b,c});
        g[b].push_back({a,c});
        pr.push_back({a,b});
    }
    for(int i=0;i<s;i++)
    {
        int pom;
        cin>>pom;
        ins.insert(pom-1);
    }
    while(q--)
    {
        int idxe,st;
        cin>>idxe>>st;
        idxe--;
        st--;
        int n1=pr[idxe].first;
        int n2=pr[idxe].second;
        if(n<1100)
        {
            ///kolku e odalecen od S
            priority_queue<node>Q;
            Q.push(node(st,0));
            int d[n];
            for(int pi=0;pi<n;pi++)
            {
                d[pi]=2e9;
            }
            d[st]=0;
            bool ok=false;
            while(!Q.empty())
            {
                node teme=Q.top();Q.pop();
                if(teme.idx==e)
                {
                    cout<<"escaped"<<endl;
                    ok=true;
                    break;
                }
                for(auto ax:g[teme.idx])
                {
                    if((teme.idx==n1 && ax.first==n2) || (teme.idx==n2 && ax.first==n1))
                    {
                        continue;
                    }
                    if(teme.dis+ax.second<d[ax.first])
                    {
                        d[ax.first]=teme.dis+ax.second;
                        Q.push(node(ax.first,d[ax.first]));
                    }
                }
            }
            int ans=2e9;
            for(auto pom:ins)
            {
                ans=min(ans, d[pom]);
            }
            if(!ok)
            {
                if(ans!=2e9)
                cout<<ans<<endl;
                else
                {
                    cout<<"oo"<<endl;
                }
            }
        }
    }
	return 0;
}

• Subtask 1: 0 / 9
• Subtask 2: 0 / 27
• Subtask 3: 0 / 23
• Subtask 4: 0 / 41