Submission #970946

#	Time	Username	Problem	Language	Result	Execution time	Memory
970946		CSQ31	Airplane (NOI23_airplane)	C++17	100 / 100	276 ms	26976 KiB

Main

#include<bits/stdc++.h>
using namespace std;
#define pb push_back
#define fi first
#define se second
#define sz(a) (int)(a.size())
#define all(a) a.begin(),a.end()
#define lb lower_bound
#define ub upper_bound
#define owo ios_base::sync_with_stdio(0);cin.tie(0);
#define MOD (ll)(998244353)
#define INF (ll)(1e18)
#define debug(...) fprintf(stderr, __VA_ARGS__),fflush(stderr)
#define time__(d) for(long blockTime = 0; (blockTime == 0 ? (blockTime=clock()) != 0 : false);\
debug("%s time : %.4fs\n", d, (double)(clock() - blockTime) / CLOCKS_PER_SEC))
typedef long long int ll;
typedef long double ld;
typedef pair<ll,ll> PII;
typedef pair<int,int> pii;
typedef vector<vector<int>> vii;
typedef vector<vector<ll>> VII;
const int MAXN = 2e5+5;
vector<int>adj[MAXN];
ll d0[MAXN],d1[MAXN],a[MAXN];
int main()
{
    owo
    int n,m;
    cin>>n>>m;
    for(int i=0;i<n;i++)cin>>a[i];
    for(int i=0;i<m;i++){
        int v,u;
        cin>>v>>u;
        v--;
        u--;
        adj[v].pb(u);
        adj[u].pb(v);
    }
    for(int i=0;i<n;i++)d0[i] = d1[i] = 1e18;

    d0[0] = 0;
    priority_queue<PII,vector<PII>,greater<PII>>pq;
    pq.push({0,0});
    while(!pq.empty()){
        ll d = pq.top().fi;
        int v = pq.top().se;
        pq.pop();
        if(d != d0[v])continue;
        for(int x:adj[v]){
            if(d+1 <= a[x] && a[x] < d0[x]){
                d0[x] = a[x];
                pq.push({a[x],x});
            }else if(d+1 > a[x] && d+1 < d0[x]){
                d0[x] = d+1;
                pq.push({d+1,x});
            }
        }
    }
    d1[n-1] = 0;
    pq.push({0,n-1});
    while(!pq.empty()){
        ll d = pq.top().fi;
        int v = pq.top().se;
        pq.pop();
        if(d != d1[v])continue;
        for(int x:adj[v]){
            if(d+1 <= a[x] && a[x] < d1[x]){
                d1[x] = a[x];
                pq.push({a[x],x});
            }else if(d+1 > a[x] && d+1 < d1[x]){
                d1[x] = d+1;
                pq.push({d+1,x});
            }
        }
    }
    ll ans = INF;
    for(int i=0;i<n;i++){
        ans = min(ans,2*max(d0[i],d1[i]));
        for(int x:adj[i]){
            ans = min(ans,2*max(d0[i],d1[x])+1);
        }
    }
    cout<<ans<<'\n';
}

• Subtask 1: 22 / 22
• Subtask 2: 10 / 10
• Subtask 3: 31 / 31
• Subtask 4: 37 / 37