Submission #553462

#	Time	Username	Problem	Language	Result	Execution time	Memory
553462		ala2	Jakarta Skyscrapers (APIO15_skyscraper)	C++14	36 / 100	307 ms	262144 KiB

skyscraper

#include <bits/stdc++.h>
    #define int long long
    #define F first
    #define S second
    #define pb push_back
    #define B begin()
    #define E end()

    using namespace std;
    int a[300010];
    int b[300010];
    vector<pair<int,int>>v[100100];
    int dist(int i,int j)
    {
        return abs(a[j]-a[i]);
    }
    int dis[100100];
    const int inf=1e17;
    signed main()
    {
       ios_base::sync_with_stdio();
       cin.tie(0);
       cout.tie(0);
        int n,m;
        cin>>n>>m;
        int ss,ee;
        for(int i=1;i<=m;i++)
        {
            cin>>a[i]>>b[i];
            if(i==1)
                ss=a[i];
            if(i==2)
                ee=a[i];


        }
        for(int i=1;i<=m;i++)
        {
            int g=0;
            for(int j=a[i]-b[i];j>=0;j-=b[i])
            {
                g++;
                //cout<<"    "<<a[i]<<"   "<<j<<"  "<<g<<endl;
                v[a[i]].pb({g,j});
            }
            g=1;
            for(int j=a[i]+b[i];j<n;j+=b[i])
            {
              //  cout<<"            "<<a[i]<<"  "<<j<<"   "<<g<<endl;
                v[a[i]].pb({g,j});
                g++;
            }
        }

        if(ss==ee)
        {
            cout<<0<<endl;
            return 0;
        }
        for(int i=0;i<=n;i++)
            sort(v[i].B,v[i].E);
        for(int i=0;i<=n+1;i++)
        {
            dis[i]=inf;
        }
        dis[ss]=0;
        priority_queue<pair<int,int>,vector<pair<int,int>>,greater<pair<int,int>>>q;
        q.push({0,ss});
        while(!q.empty())
        {
          //  cout<<"D";
            pair<int,int>x=q.top();
            q.pop();
           // cout<<"      ::::   "<<x.S<<endl;
            for(auto i:v[x.S])
            {
                int ned=x.F+i.F;            //    cout<<"         "<<i.F<<"   "<<ned<<endl;

                if(ned<dis[i.S])
                {
                    //cout<<"              "<<i.S<<"   "<<ned<<"    "<<
                    dis[i.S]=ned;
                    q.push({ned,i.S});
                }
            }


        }
        if(dis[ee]<inf)
        cout<<dis[ee]<<endl;
        else cout<<-1<<endl;

    }

Compilation message (stderr)

skyscraper.cpp: In function 'int main()':
skyscraper.cpp:66:16: warning: 'ss' may be used uninitialized in this function [-Wmaybe-uninitialized]
   66 |         dis[ss]=0;
      |         ~~~~~~~^~
skyscraper.cpp:89:18: warning: 'ee' may be used uninitialized in this function [-Wmaybe-uninitialized]
   89 |         if(dis[ee]<inf)
      |            ~~~~~~^

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