Submission #245566

#	Time	Username	Problem	Language	Result	Execution time	Memory
245566		mat_v	Jakarta Skyscrapers (APIO15_skyscraper)	C++14	100 / 100	172 ms	65768 KiB

skyscraper

#pragma GCC optimization ("O3")
#pragma GCC optimize("Ofast")


#include <bits/stdc++.h>
#include <ext/pb_ds/assoc_container.hpp>
#include <ext/pb_ds/tree_policy.hpp>
#include <ext/rope>

#define ff(i,a,b) for(int (i) = (a); (i) <= (b); ++(i))
#define fb(i,a,b) for(int (i) = (a); (i) >= (b); --(i))
#define mod 998244353
#define xx first
#define yy second
#define all(a) (a).begin(), (a).end()
#define pb push_back
#define ll long long
#define pii pair<int,int>


using namespace std;
using namespace __gnu_pbds;
typedef tree<int, null_type, less<int>,rb_tree_tag, tree_order_statistics_node_update> ordered_set;/// find_by_order(x)(x+1th) , order_of_key() (strictly less)
mt19937 rnd(chrono::steady_clock::now().time_since_epoch().count());




int n,m;
pii niz[30005];

vector<pii> graf[30005];
int dist[30005];



set<int> pos[30005];
priority_queue<pii>pq;

int main()
{

    //ios_base::sync_with_stdio(false); cin.tie(0);

    cin >> m >> n;
    ff(i,1,n){
        cin >> niz[i].xx >> niz[i].yy;
        pos[niz[i].xx].insert(niz[i].yy);
    }

    ff(i,0,m - 1){
        for(auto c:pos[i]){

            for(int j = i + c; j < m; j += c){
                graf[i].pb({j, (j - i) / c});
                if(pos[j].count(c))break;
            }
            for(int j = i - c; j >= 0; j -= c){
                graf[i].pb({j, (i - j) / c});
                if(pos[j].count(c))break;
            }
        }
    }



    ff(i,0,m - 1)dist[i] = 1e9;
    dist[niz[1].xx] = 0;
    pq.push({0,niz[1].xx});
    while(!pq.empty()){
        pii sta = pq.top();
        pq.pop();
        sta.xx = -sta.xx;
        if(dist[sta.yy] != sta.xx)continue;
        for(auto c:graf[sta.yy]){
            if(dist[c.xx] > sta.xx + c.yy){
                dist[c.xx] = sta.xx + c.yy;
                pq.push({-dist[c.xx], c.xx});
            }
        }
    }
    if(dist[niz[2].xx] == 1e9)cout << -1 << "\n";
    else cout << dist[niz[2].xx] << "\n";
    return 0;
}

Compilation message (stderr)

skyscraper.cpp:2:0: warning: ignoring #pragma GCC optimization [-Wunknown-pragmas]
 #pragma GCC optimization ("O3")

• Subtask 1: 10 / 10
• Subtask 2: 12 / 12
• Subtask 3: 14 / 14
• Subtask 4: 21 / 21
• Subtask 5: 43 / 43