Submission #1084147

#	Time	Username	Problem	Language	Result	Execution time	Memory
1084147		kokoue	Evacuation plan (IZhO18_plan)	C++14	100 / 100	369 ms	96704 KiB

plan

#include<bits/stdc++.h>
#define maxn 100010
#define ff first
#define ss second
using namespace std;
int n,m,k,q;
bool is_npp[maxn];
vector<pair<int,int>> edges[maxn];
vector<long long> sp(maxn,INT_MAX);
vector<int> npp;
int parent[maxn];
struct Query
{
    int qu,qv,idx;
};
queue<Query> quer[maxn];

void dijkstra()
{
    priority_queue<pair<long long,int>> q;
    vector<long long> dist(n+1,INT_MAX);
    for(int i=0;i<npp.size();i++)
    {
        q.push({0,npp[i]});
        dist[npp[i]]=0;
        sp[npp[i]]=0;
    }
    while(!q.empty())
    {
        int curr=q.top().second;
        long long currDist=-q.top().first;
        q.pop();
        if(dist[curr]<currDist) continue;
        for(auto edge:edges[curr])
        {
            int next=edge.first;
            int weight=edge.second;
            if(dist[curr]+weight<dist[next])
            {
                dist[next]=dist[curr]+weight;
                sp[next]=min(sp[next],dist[next]);
                q.push({-dist[next],next});
            }
        }
    }
}
int findd(int u)
{
    if(parent[u]==0) return u;
    return parent[u]=findd(parent[u]);
}
int ans[maxn];
void unite(int u,int v,int mn)
{
    u=findd(u);
    v=findd(v);
    if(u==v) return;
    if(quer[u].size()<quer[v].size()) swap(u,v);
    parent[v]=u;
    while(!quer[v].empty())
    {
        Query curr=quer[v].front();
        quer[v].pop();
        if(findd(curr.qu)==findd(curr.qv) && ans[curr.idx]==-1) {ans[curr.idx]=mn;continue;}
        if(ans[curr.idx]==-1) quer[u].push(curr);
    }
}
vector<pair<int,int>> finale;
int main()
{
    ios_base::sync_with_stdio(false);
    cin.tie(0);
    cin>>n>>m;
    int ai,bi,wi;
    for(int i=0;i<m;i++)
    {
        cin>>ai>>bi>>wi;
        edges[ai].push_back({bi,wi});
        edges[bi].push_back({ai,wi});
    }
    cin>>k;
    for(int i=0;i<k;i++)
    {
        int npp1;
        cin>>npp1;
        is_npp[npp1]=true;
        npp.push_back(npp1);
    }
    dijkstra();
    cin>>q;
    for(int i=0;i<q;i++)
    {
        ans[i]=-1;
        Query curr;
        cin>>curr.qu>>curr.qv;
        curr.idx=i;
        quer[curr.qu].push(curr);
        quer[curr.qv].push(curr);
    }
    for(int i=1;i<=n;i++)
    {
        finale.push_back({sp[i],i});
    }
    sort(finale.begin(),finale.end());
    reverse(finale.begin(),finale.end());
    for(int i=0;i<finale.size();i++)
    {
        auto curr=finale[i];
        for(auto e:edges[curr.ss])
        {
            if(curr.ff<=sp[e.ff])
            {
                unite(curr.ss,e.ff,curr.ff);
            }
        }
    }
    for(int i=0;i<q;i++)
    {
        cout<<ans[i]<<"\n";
    }
}
/*
9 12
1 9 4
1 2 5
2 3 7
2 4 3
4 3 6
3 6 4
8 7 10
6 7 5
5 8 1
9 5 7
5 4 12
6 8 2
2
4 7
5
1 6
5 3
4 8
5 8
1 5
*/

Compilation message (stderr)

plan.cpp: In function 'void dijkstra()':
plan.cpp:22:18: warning: comparison of integer expressions of different signedness: 'int' and 'std::vector<int>::size_type' {aka 'long unsigned int'} [-Wsign-compare]
   22 |     for(int i=0;i<npp.size();i++)
      |                 ~^~~~~~~~~~~
plan.cpp: In function 'int main()':
plan.cpp:106:18: warning: comparison of integer expressions of different signedness: 'int' and 'std::vector<std::pair<int, int> >::size_type' {aka 'long unsigned int'} [-Wsign-compare]
  106 |     for(int i=0;i<finale.size();i++)
      |                 ~^~~~~~~~~~~~~~

• Subtask 1: 10 / 10
• Subtask 2: 13 / 13
• Subtask 3: 12 / 12
• Subtask 4: 19 / 19
• Subtask 5: 46 / 46