Submission #933342

#	Time	Username	Problem	Language	Result	Execution time	Memory
933342		Hanksburger	Jakarta Skyscrapers (APIO15_skyscraper)	C++17	100 / 100	126 ms	69432 KiB

skyscraper

#include <bits/stdc++.h>
using namespace std;
vector<pair<pair<int, int>, int> > vec;
priority_queue<pair<int, int> > pq;
vector<pair<int, int> > adj[30005];
int dist[30005], final[30005];
vector<int> tmp;
int main()
{
    ios::sync_with_stdio(0);
    cin.tie(0);
    cout.tie(0);
    int n, m, s, e;
    cin >> n >> m;
    for (int i=0; i<m; i++)
    {
        int a, b;
        cin >> a >> b;
        vec.push_back({{b, a%b}, a});
        if (i==0)
            s=a;
        if (i==1)
            e=a;
    }
    sort(vec.begin(), vec.end());
    for (int i=0; i<vec.size(); i++)
    {
        tmp.push_back(vec[i].second);
        if (i==vec.size()-1 || vec[i].first!=vec[i+1].first)
        {
            int a=vec[i].first.first, b=vec[i].first.second, ind=0;
            for (int j=b; j<n; j+=a)
            {
                while (ind<tmp.size() && tmp[ind]<=j)
                    ind++;
                if (ind==tmp.size())
                    break;
                adj[tmp[ind]].push_back({j, (tmp[ind]-j)/a});
            }
            ind=tmp.size()-1;
            for (int j=(n-b-1)/a*a+b; j>=0; j-=a)
            {
                while (ind>=0 && tmp[ind]>=j)
                    ind--;
                if (ind==-1)
                    break;
                adj[tmp[ind]].push_back({j, (j-tmp[ind])/a});
            }
            tmp.clear();
        }
    }
    for (int i=0; i<n; i++)
        dist[i]=1e9;
    dist[s]=0;
    pq.push({-dist[s], s});
    while (!pq.empty())
    {
        int u=pq.top().second;
        pq.pop();
        if (final[u])
            continue;
        final[u]=1;
        for (int i=0; i<adj[u].size(); i++)
        {
            int v=adj[u][i].first, w=adj[u][i].second;
            if (dist[u]+w<dist[v])
            {
                dist[v]=dist[u]+w;
                pq.push({-dist[v], v});
            }
        }
    }
    if (dist[e]==1e9)
        cout << -1;
    else
        cout << dist[e];
}

Compilation message (stderr)

skyscraper.cpp: In function 'int main()':
skyscraper.cpp:26:20: warning: comparison of integer expressions of different signedness: 'int' and 'std::vector<std::pair<std::pair<int, int>, int> >::size_type' {aka 'long unsigned int'} [-Wsign-compare]
   26 |     for (int i=0; i<vec.size(); i++)
      |                   ~^~~~~~~~~~~
skyscraper.cpp:29:14: warning: comparison of integer expressions of different signedness: 'int' and 'std::vector<std::pair<std::pair<int, int>, int> >::size_type' {aka 'long unsigned int'} [-Wsign-compare]
   29 |         if (i==vec.size()-1 || vec[i].first!=vec[i+1].first)
      |             ~^~~~~~~~~~~~~~
skyscraper.cpp:34:27: warning: comparison of integer expressions of different signedness: 'int' and 'std::vector<int>::size_type' {aka 'long unsigned int'} [-Wsign-compare]
   34 |                 while (ind<tmp.size() && tmp[ind]<=j)
      |                        ~~~^~~~~~~~~~~
skyscraper.cpp:36:24: warning: comparison of integer expressions of different signedness: 'int' and 'std::vector<int>::size_type' {aka 'long unsigned int'} [-Wsign-compare]
   36 |                 if (ind==tmp.size())
      |                     ~~~^~~~~~~~~~~~
skyscraper.cpp:63:24: warning: comparison of integer expressions of different signedness: 'int' and 'std::vector<std::pair<int, int>, std::allocator<std::pair<int, int> > >::size_type' {aka 'long unsigned int'} [-Wsign-compare]
   63 |         for (int i=0; i<adj[u].size(); i++)
      |                       ~^~~~~~~~~~~~~~
skyscraper.cpp:73:15: warning: 'e' may be used uninitialized in this function [-Wmaybe-uninitialized]
   73 |     if (dist[e]==1e9)
      |         ~~~~~~^

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