Submission #967392

#	Time	Username	Problem	Language	Result	Execution time	Memory
967392		irmuun	Evacuation plan (IZhO18_plan)	C++17	100 / 100	997 ms	71332 KiB

plan

#include<bits/stdc++.h>

using namespace std;

#define ll long long
#define pb push_back
#define ff first
#define ss second
#define all(s) s.begin(),s.end()
#define rall(s) s.rbegin(),s.rend()

struct dsu{
    ll n;
    vector<ll>sz,par;
    dsu(ll n):n(n){
        sz.resize(n+1);
        par.resize(n+1);
        reset();
    }
    void reset(){
        fill(all(sz),1);
        iota(all(par),0);
    }
    ll find(ll x){
        if(x==par[x]) return x;
        return par[x]=find(par[x]);
    }
    bool same(ll x,ll y){
        x=find(x);
        y=find(y);
        return x==y;
    }
    void merge(ll x,ll y){
        x=find(x);
        y=find(y);
        if(x!=y){
            if(x<y) swap(x,y);
            par[y]=x;
            sz[x]+=sz[y];
        }
    }
};

int main(){
    ll n,m;
    cin>>n>>m;
    vector<pair<ll,ll>>adj[n+5];
    vector<array<ll,2>>edge;
    for(ll i=1;i<=m;i++){
        ll a,b,w;
        cin>>a>>b>>w;
        edge.pb({a,b});
        adj[a].pb({b,w});
        adj[b].pb({a,w});
    }
    ll k;
    cin>>k;
    ll g[k+5];
    ll dist[n+5];
    fill(dist,dist+n+1,1e18);
    set<pair<ll,ll>>st;
    for(ll i=1;i<=k;i++){
        cin>>g[i];
        st.insert({0,g[i]});
        dist[g[i]]=0;
    }
    while(!st.empty()){
        auto [y,i]=*st.begin();
        st.erase(st.begin());
        if(dist[i]!=y) continue;
        for(auto [j,w]:adj[i]){
            if(dist[i]+w<dist[j]){
                dist[j]=dist[i]+w;
                st.insert({dist[j],j});
            }
        }
    }
    vector<array<ll,3>>ord;
    for(auto [a,b]:edge){
        ord.pb({min(dist[a],dist[b]),a,b});
    }
    sort(rall(ord));
    ll q;
    cin>>q;
    vector<array<ll,3>>ask;
    ll s[q+5],t[q+5];
    for(ll i=1;i<=q;i++){
        cin>>s[i]>>t[i];
        ask.pb({0,(ll)1e9,i});
    }
    ll lg=30;
    dsu ds(n);
    while(lg--){
        ds.reset();
        sort(rall(ask));
        ll cur=0;
        for(ll i=0;i<ask.size();i++){
            ll l=ask[i][0],r=ask[i][1],j=ask[i][2];
            if(l==r) continue;
            ll mid=(l+r+1)/2;
            while(cur<m&&ord[cur][0]>=mid){
                ds.merge(ord[cur][1],ord[cur][2]);
                cur++;
            }
            if(ds.same(s[j],t[j])){
                ask[i]={mid,r,j};
            }
            else{
                ask[i]={l,mid-1,j};
            }
        }
    }
    ll ans[q+5];
    for(ll i=0;i<q;i++){
        ans[ask[i][2]]=ask[i][0];
    }
    for(ll i=1;i<=q;i++){
        cout<<ans[i]<<"\n";
    }
}

Compilation message (stderr)

plan.cpp: In function 'int main()':
plan.cpp:97:21: warning: comparison of integer expressions of different signedness: 'long long int' and 'std::vector<std::array<long long int, 3> >::size_type' {aka 'long unsigned int'} [-Wsign-compare]
   97 |         for(ll i=0;i<ask.size();i++){
      |                    ~^~~~~~~~~~~

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