Submission #463517

#	Time	Username	Problem	Language	Result	Execution time	Memory
463517		zaneyu	Evacuation plan (IZhO18_plan)	C++14	100 / 100	2508 ms	32408 KiB

plan

/*input
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
*/
#include<bits/stdc++.h>
#include <ext/pb_ds/assoc_container.hpp>
#include <ext/pb_ds/tree_policy.hpp>
using namespace std;
using namespace __gnu_pbds;
#pragma GCC optimize("unroll-loops,no-stack-protector")
//order_of_key #of elements less than x
// find_by_order kth element
typedef long long int ll;
#define ld long double
#define pii pair<int,int>
typedef tree<pii, null_type, less<pii>, rb_tree_tag, tree_order_statistics_node_update> indexed_set;
#define f first
#define s second
#define pb push_back
#define REP(i,n) for(ll i=0;i<n;i++)
#define REP1(i,n) for(int i=1;i<=n;i++)
#define FILL(n,x) memset(n,x,sizeof(n))
#define ALL(_a) _a.begin(),_a.end()
#define sz(x) (int)x.size()
const ll maxn=1e5+5;
const ll maxlg=__lg(maxn)+2;
const ll INF64=4e18;
const int INF=0x3f3f3f3f;
const ll MOD=1e9+7;
const ld PI=acos(-1);
const ld eps=1e-9;
#define lowb(x) x&(-x)
#define MNTO(x,y) x=min(x,(__typeof__(x))y)
#define MXTO(x,y) x=max(x,(__typeof__(x))y)
#define SORT_UNIQUE(c) (sort(c.begin(),c.end()), c.resize(distance(c.begin(),unique(c.begin(),c.end()))))
#define GET_POS(c,x) (lower_bound(c.begin(),c.end(),x)-c.begin())
template<typename T1,typename T2>
ostream& operator<<(ostream& out,pair<T1,T2> P){
    out<<P.f<<' '<<P.s;
    return out;
}
template<typename T>
ostream& operator<<(ostream& out,vector<T> V){
    REP(i,sz(V)) out<<V[i]<<((i!=sz(V)-1)?" ":"");
    return out;
}
int mult(ll a,ll b){
    if(a<0) a+=MOD;
    return (a*b)%MOD;
}
ll mypow(ll a,ll b){
    if(b<=0) return 1;
    ll res=1LL;
    while(b){
        if(b&1) res=mult(res,a);
        a=mult(a,a);
        b>>=1;
    }
    return res;
}
int dist[maxn];
vector<pii> v[maxn];
pii ans[maxn];
int par[maxn];
pii qq[maxn];
int find(int u){
    if(par[u]==u) return u;
    return par[u]=find(par[u]);
}
void merge(int a,int b){
    a=find(a),b=find(b);
    if(a==b) return;
    par[a]=b;
}
int32_t main(){
    ios::sync_with_stdio(false),cin.tie(0);
    int n,m;
    cin>>n>>m;
    REP(i,m){
        int a,b,c;
        cin>>a>>b>>c;
        --a,--b;
        v[a].pb({b,c});
        v[b].pb({a,c});
    }
    int k;
    cin>>k;
    priority_queue<pii,vector<pii>,greater<pii>> pq;
    REP(i,n) dist[i]=INF;
    REP(i,k){
        int x;
        cin>>x;
        --x;
        dist[x]=0;
        pq.push({0,x});
    }
    while(!pq.empty()){
        int z=pq.top().s;
        pq.pop();
        for(auto x:v[z]){
            if(dist[x.f]>dist[z]+x.s){
                dist[x.f]=dist[z]+x.s;
                pq.push({dist[x.f],x.f});
            }
        }
    }
    int q;
    cin>>q;
    REP(i,q){
        int a,b;
        cin>>a>>b;
        --a,--b;
        qq[i]={a,b};
        ans[i]={0,INF};
    }
    vector<pii> vv;
    REP(i,n) vv.pb({dist[i],i});
    sort(ALL(vv));
    reverse(ALL(vv));
    REP(asd,30){
        REP(i,n) par[i]=i;
        vector<pii> qs; 
        REP(i,q) qs.pb({(ans[i].f+ans[i].s+1)/2,i});
        sort(ALL(qs));
        reverse(ALL(qs));
        int p=0;
        while(p<q and qs[p].f>vv[0].f){
            int z=qs[p].s;
            pii a=qq[z];
            if(find(a.f)==find(a.s)) ans[z].f=qs[p].f;
            else ans[z].s=qs[p].f-1;
            ++p;   
        }
        REP(i,n){
            int z=vv[i].s;
            for(auto x:v[z]){
                if(dist[x.f]>=dist[z]) merge(x.f,z);
            }
            while(p<q and qs[p].f<=vv[i].f and qs[p].f>vv[i+1].f){
                int z=qs[p].s;
                pii a=qq[z];
                if(find(a.f)==find(a.s)) ans[z].f=qs[p].f;
                else ans[z].s=qs[p].f-1;
                ++p;
            }
        }
        //REP(i,q) cout<<ans[i].f<<' '<<ans[i].s<<'\n'; 
    }
    REP(i,q) cout<<ans[i].f<<'\n';
}   

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