Submission #45499

#	Time	Username	Problem	Language	Result	Execution time	Memory
45499		dqhungdl	Jakarta Skyscrapers (APIO15_skyscraper)	C++17	57 / 100	44 ms	21464 KiB

skyscraper

#include <bits/stdc++.h>
using namespace std;

typedef pair<int,int> ii;
int n,m,S,T,d[2005][2005];
bool Visited[30005],Free[2005][2005];
vector<int> g[30005];
queue<ii> Q;

int main()
{
    ios_base::sync_with_stdio(false);
    //freopen("TEST.INP","r",stdin);
    cin>>n>>m;
    int pos,step;
    for(int i=1;i<=m;i++)
    {
        cin>>pos>>step;
        g[pos+1].push_back(step);
        if(i==1)
            S=pos+1;
        if(i==2)
            T=pos+1;
    }
    for(int i=0; i<g[S].size(); i++)
    {
        Free[S][g[S][i]]=true;
        Q.push(ii(S,g[S][i]));
    }
    while(Q.size()>0)
    {
        int u=Q.front().first;
        int v=Q.front().second;
        Q.pop();
        if(u==T)
        {
            cout<<d[u][v];
            return 0;
        }
        if(Visited[u]==false)
        {
            Visited[u]=true;
            for(int i=0; i<g[u].size(); i++)
            {
                if(u-g[u][i]>=1&&Free[u-g[u][i]][g[u][i]]==false)
                {
                    Free[u-g[u][i]][g[u][i]]=true;
                    d[u-g[u][i]][g[u][i]]=d[u][v]+1;
                    Q.push(ii(u-g[u][i],g[u][i]));
                }
                if(u+g[u][i]<=n&&Free[u+g[u][i]][g[u][i]]==false)
                {
                    Free[u+g[u][i]][g[u][i]]=true;
                    d[u+g[u][i]][g[u][i]]=d[u][v]+1;
                    Q.push(ii(u+g[u][i],g[u][i]));
                }
            }
        }
        if(u-v>=1&&Free[u-v][v]==false)
        {
            Free[u-v][v]=true;
            d[u-v][v]=d[u][v]+1;
            Q.push(ii(u-v,v));
        }
        if(u+v<=n&&Free[u+v][v]==false)
        {
            Free[u+v][v]=true;
            d[u+v][v]=d[u][v]+1;
            Q.push(ii(u+v,v));
        }
    }
    cout<<-1;
}

Compilation message (stderr)

skyscraper.cpp: In function 'int main()':
skyscraper.cpp:25:19: warning: comparison between signed and unsigned integer expressions [-Wsign-compare]
     for(int i=0; i<g[S].size(); i++)
                  ~^~~~~~~~~~~~
skyscraper.cpp:43:27: warning: comparison between signed and unsigned integer expressions [-Wsign-compare]
             for(int i=0; i<g[u].size(); i++)
                          ~^~~~~~~~~~~~

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