Submission #714410

#	Time	Username	Problem	Language	Result	Execution time	Memory
714410		Ferid20072020	Event Hopping (BOI22_events)	C++14	10 / 100	1592 ms	399832 KiB

events

/////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////
//#pragma GCC optimize("O3,unroll-loops")
//#pragma GCC target("avx,avx2,fma")

#include <bits/stdc++.h>

using namespace std;

#define ll          long long 
#define ull         unsigned long long 
#define ld          long double 
#define ui          unsigned int 
#define f           first
#define s           second
#define ins         insert
#define pb          push_back
#define mp          make_pair
#define ln          '\n'
#define int         ll
#define pii         pair<int , int> 
#define INF         LLONG_MAX
#define vv(a)       vector<a>
#define pp(a, b)    pair<a, b>
#define pq(a)       priority_queue<a>
#define qq(a)       queue<a>
#define ss(a)       set<a>
#define mss(a)      multiset<a>
#define mm(a, b)    map<a, b>
#define mmm(a , b)  multimap<a , b>
#define sz(x)       (x).size()
#define all(x)      (x).begin() , (x).end()
#define fastio                    \
    ios_base::sync_with_stdio(0); \
    cin.tie(0);                   \
    cout.tie(0);

/////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////

const int MAX = 5010;
vv(pii) a(MAX);
vv(vv(int)) g(MAX);
vv(vv(int)) dist(MAX , vv(int) (MAX , -1));

void BFS(int node){
    dist[node][node] = 0;
    queue<int> Q;   
    Q.push(node);
    while(!Q.empty()){
        int from = Q.front();
        Q.pop();
        for(auto to : g[from]){
            if(dist[node][to] == -1){
                dist[node][to] = dist[node][from] + 1;
                Q.push(to);
            }
        }
    }
}

void solve(){
    int n , q;
    cin >> n >> q;
    for(int i=0 ; i<n ; i++){
        cin >> a[i].f >> a[i].s;
    }   
    for(int i=0 ; i<n ; i++){
        for(int j=0 ; j<n ; j++){
            if(i != j){
                if(a[j].f <= a[i].s && a[j].s >= a[i].s){
                    g[i].pb(j);
                }
            }
        }
    }
    for(int i=0 ; i<n ; i++){
        BFS(i);
    }
    //cout << dist[0][3] << ln;
    for(int i=0 ; i<q ; i++){
        int u , v;
        cin >> u >> v;
        u--; v--;
        if(dist[u][v] == -1){
            cout << "impossible" << ln;
        }
        else{
            cout << dist[u][v] << ln;
        }
    }
}


signed main(){
    fastio

    int t = 1;
    //cin >> t;
    while(t--){
        solve();
    }

    return 0;
}

• Subtask 1: 0 / 10
• Subtask 2: 10 / 10
• Subtask 3: 0 / 15
• Subtask 4: 0 / 15
• Subtask 5: 0 / 20
• Subtask 6: 0 / 30