Submission #31541

#	Time	Username	Problem	Language	Result	Execution time	Memory
31541		Kanvie	Senior Postmen (BOI14_postmen)	C++14	38 / 100	1091 ms	16812 KiB

postmen

#include<bits/stdc++.h>
using namespace std;
#define fi first
#define se second
typedef pair<int,int> pii;
int n,m,vv,u,cnt;
vector<pair<int,int> >v[500001];
bool visit[500001],fi,edge[500001];
vector<int>ans;
stack<int>s;
bool chk(int x)
{
    if(!edge[x]){edge[x]=true;return true;}
    else return false;
}
int x,y;
int main()
{
    ios_base::sync_with_stdio(false);
    cin>>n>>m;
    for(int i=1;i<=m;++i)
    {
        cin>>x>>y;
        ++cnt;
        v[x].push_back({y,cnt});
        v[y].push_back({x,cnt});
    }
    s.push(1);
    while(!s.empty())
    {
        u=s.top();
        for(int i=0;i<v[u].size();++i)
        {
            vv=v[u][i].fi;
            if(chk(v[u][i].se))break;
            if(i==v[u].size()-1)vv=-1;
        }
        if(vv!=-1)s.push(vv);
        else {s.pop();ans.push_back(u);}
    }
    fi=false;
    for(int i=0;i<ans.size();++i)
    {
        if(!visit[ans[i]])
        {
            s.push(ans[i]);
            visit[ans[i]]=true;
        }
        else
        {
            if(fi)cout<<endl;
            else fi=true;
            while(1)
            {
                if(s.top()!=ans[i])cout<<s.top()<<' ';
                else cout<<s.top();
                if(s.top()!=ans[i]){visit[s.top()]=false;s.pop();}
                else break;
            }
        }
    }
}

Compilation message (stderr)

postmen.cpp: In function 'int main()':
postmen.cpp:32:22: warning: comparison between signed and unsigned integer expressions [-Wsign-compare]
         for(int i=0;i<v[u].size();++i)
                     ~^~~~~~~~~~~~
postmen.cpp:36:17: warning: comparison between signed and unsigned integer expressions [-Wsign-compare]
             if(i==v[u].size()-1)vv=-1;
                ~^~~~~~~~~~~~~~~
postmen.cpp:42:18: warning: comparison between signed and unsigned integer expressions [-Wsign-compare]
     for(int i=0;i<ans.size();++i)
                 ~^~~~~~~~~~~

• Subtask 1: 38 / 38
• Subtask 2: 0 / 17
• Subtask 3: 0 / 45