Submission #112944

#	Time	Username	Problem	Language	Result	Execution time	Memory
112944		nafis_shifat	Jakarta Skyscrapers (APIO15_skyscraper)	C++14	100 / 100	54 ms	12544 KiB

skyscraper

#include<bits/stdc++.h>
#define mx 30009
#define pii pair<int,int>
using namespace std;
int main()
{
    
    int n,m;
    cin>>n>>m;
    int b[m+1],p[m+1];
    int sp[n+1]={};
    vector<pii> edg[mx];
    set<int> mp[30009];
    for(int i=0;i<m;i++)
    {
        scanf("%d%d",&b[i],&p[i]);
        
        sp[b[i]]=p[i];
        
        
        
        
    }
    
    for(int i=0;i<m;i++)
    {
        int k=0;
        if(mp[b[i]].count(p[i]))continue;
        for(int j=b[i]+p[i];j<n;j+=p[i])
        {
            k++;
            if(sp[j]!=0 )
               edg[b[i]].push_back({j,k});
            if(mp[j].count(p[i]))break;
        }
        k=0;
        for(int j=b[i]-p[i];j>=0;j-=p[i])
        {
            k++;
            if(sp[j]!=0)
               edg[b[i]].push_back({j,k});
            if(mp[j].count(p[i]))break;
        }
        
        mp[b[i]].insert(p[i]);
    }
    
   
    
    
   
    int dist[mx+1];
    for(int i=0;i<=mx;i++)dist[i]=(int)2e9;
    priority_queue<pii,vector<pii>,greater<pii>> pq;

    
    pq.push({0,b[0]});
    dist[b[0]]=0;
    int vis[mx+1]={};
    
    while(!pq.empty())
    {
        int u=pq.top().second;
       
        pq.pop();
        if(u==b[1])
        {
            cout<<dist[u]<<endl;
            return 0;
        }
        if(vis[u])continue;
        vis[u]=1;
        for(int i=0;i<edg[u].size();i++)
        {
            
            if(dist[edg[u][i].first]>dist[u]+edg[u][i].second)
            {
                dist[edg[u][i].first]=dist[u]+edg[u][i].second;
               
                pq.push({dist[edg[u][i].first],edg[u][i].first});
            }
        }
    }
    
    cout<<-1<<endl;
    
    
}

Compilation message (stderr)

skyscraper.cpp: In function 'int main()':
skyscraper.cpp:73:22: warning: comparison between signed and unsigned integer expressions [-Wsign-compare]
         for(int i=0;i<edg[u].size();i++)
                     ~^~~~~~~~~~~~~~
skyscraper.cpp:16:14: warning: ignoring return value of 'int scanf(const char*, ...)', declared with attribute warn_unused_result [-Wunused-result]
         scanf("%d%d",&b[i],&p[i]);
         ~~~~~^~~~~~~~~~~~~~~~~~~~

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