Submission #883560

#	Time	Username	Problem	Language	Result	Execution time	Memory
883560		SalihSahin	Jakarta Skyscrapers (APIO15_skyscraper)	C++14	100 / 100	567 ms	7884 KiB

skyscraper

#include<bits/stdc++.h>
#define pb push_back
#define int long long
#define mp make_pair
 
using namespace std;
const int inf = 1e18;
const int mod = 1e9 + 7;
const int N = 3e4 + 5;
 
vector<int> adj[N];
 
int32_t main(){
    ios_base::sync_with_stdio(false), cin.tie();
    int n, m;
    cin>>n>>m;
    int start = 0, finish = 0;
    for(int i = 0; i < m; i++){
        int b, p;
        cin>>b>>p;
        if(i == 0) start = b;
        if(i == 1) finish = b;
 
        adj[b].pb(p);
    }
 
    priority_queue<pair<int, int> > pq;
    vector<int> best(N, inf), vis(N);
    best[start] = 0;
    pq.push(mp(0, start));
    
    while(pq.size()){
        int node = pq.top().second;
        int len = pq.top().first * (-1);
        pq.pop();
        
        if(vis[node]) continue;
        vis[node] = 1;
 
        for(auto itr: adj[node]){
            int dis = 1;
            for(int i = node + itr; i < n; i += itr){
                if(best[i] > best[node] + dis){
                    pq.push(mp(-(best[node] + dis), i));
                    best[i] = best[node] + dis;
                }
                dis++;
            }
            dis = 1;
            for(int i = node - itr; i >= 0; i -= itr){
                if(best[i] > best[node] + dis){
                    pq.push(mp(-(best[node] + dis), i));
                    best[i] = best[node] + dis;
                }
                dis++;
            }
        }
    }
 
    if(best[finish] == inf) cout<<-1<<endl;
    else cout<<best[finish]<<endl;
    return 0;
}

Compilation message (stderr)

skyscraper.cpp: In function 'int32_t main()':
skyscraper.cpp:34:13: warning: unused variable 'len' [-Wunused-variable]
   34 |         int len = pq.top().first * (-1);
      |             ^~~

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