Submission #330662

#	Time	Username	Problem	Language	Result	Execution time	Memory
330662		fammo	Jakarta Skyscrapers (APIO15_skyscraper)	C++11	0 / 100	1096 ms	1408 KiB

skyscraper

//#pragma GCC optimize("unroll-loops, Ofast")
#include <bits/stdc++.h>
using namespace std;
 
#define pb push_back
#define int long long
const int MAXN = 30000 + 7;
int n, m, p[MAXN], b[MAXN], dis[MAXN];
vector<int>adj[MAXN];
inline void dij(int root){
    set<pair<int, int>>s;
    fill(dis, dis + MAXN, LLONG_MAX/2);
    dis[root] = 0;
    s.insert({0, root});
    for(int i = 0; i < m; i ++){
        auto x = *s.begin();
        int v = x.second, d = x.first;
        s.erase(s.begin());
        for(auto p : adj[v]){
            int cnt = 1;
            for(int u = v + p; u < n; u += p){
                if(d + cnt < dis[u]){
                    s.erase({dis[u], u});
                    dis[u] = d + cnt;
                    s.insert({dis[u], u});
                }
                cnt ++;
            }
            cnt = 1;
            for(int u = v - p; u > -1; u -= p){
                if(d + cnt < dis[u]){
                    s.erase({dis[u], u});
                    dis[u] = d + cnt;
                    s.insert({dis[u], u});
                }
                cnt ++;
            }
        }
    }
    return;
}
int32_t main(){
    //ios_base::sync_with_stdio(0), cin.tie(nullptr), cout.tie(nullptr);
    //cin >> n >> m;
    scanf("%lld %lld", &n, &m);
    for(int i = 0; i < m; i ++){
        //cin >> b[i] >> p[i];
        scanf("%lld %lld", &b[i], &p[i]);
        adj[b[i]].pb(p[i]);
    }
    dij(0);
    printf("%lld\n", (dis[1] >= LLONG_MAX/2? -1ll : dis[1]));
    return 0;
}

Compilation message (stderr)

skyscraper.cpp: In function 'int32_t main()':
skyscraper.cpp:45:10: warning: ignoring return value of 'int scanf(const char*, ...)', declared with attribute warn_unused_result [-Wunused-result]
   45 |     scanf("%lld %lld", &n, &m);
      |     ~~~~~^~~~~~~~~~~~~~~~~~~~~
skyscraper.cpp:48:14: warning: ignoring return value of 'int scanf(const char*, ...)', declared with attribute warn_unused_result [-Wunused-result]
   48 |         scanf("%lld %lld", &b[i], &p[i]);
      |         ~~~~~^~~~~~~~~~~~~~~~~~~~~~~~~~~

• Subtask 1: 0 / 10
• Subtask 2: 0 / 12
• Subtask 3: 0 / 14
• Subtask 4: 0 / 21
• Subtask 5: 0 / 43