Submission #31554

#	Time	Username	Problem	Language	Result	Execution time	Memory
31554		Kanvie	Senior Postmen (BOI14_postmen)	C++14	38 / 100	1081 ms	16460 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,lol;
vector<pii>v[500001];
bool visit[500001],fi,edge[500001];
stack<int>s,ss;
inline bool chk(int x)
{
    if(!edge[x]){edge[x]=true;return true;}
    else return false;
}
int read_int(){
    char c;
    bool check = 0;
    int res = 0;
    while(1){
        c = getchar();
        if (c == '-') {check = 1; continue;}
        if (c == ' ' || c == '\n') break;
        res = res*10 + c - '0';
    }
    if (check) return -res;
    return res;
}
void push_db(int x)
{
    if(!visit[x])
    {
        ss.push(x);
        visit[x]=true;
        return;
    }
    else
    {
        if(fi)printf("\n");
        else fi=true;
        while(1)
        {
            lol=ss.top();
            if(lol!=x)printf("%d ",lol);
            else printf("%d",lol);
            if(lol!=x){visit[lol]=false;ss.pop();}
            else break;
        }
    }
}
int x,y;
int main()
{
    ios_base::sync_with_stdio(false);
    n=read_int();
    m=read_int();
    for(int i=1;i<=m;++i)
    {
        x=read_int();
        y=read_int();
        ++cnt;
        v[x].push_back({y,cnt});
        v[y].push_back({x,cnt});
    }
    s.push(1);
    fi=false;
    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();push_db(u);}
    }
}

Compilation message (stderr)

postmen.cpp: In function 'int main()':
postmen.cpp:69:22: warning: comparison between signed and unsigned integer expressions [-Wsign-compare]
         for(int i=0;i<v[u].size();++i)
                     ~^~~~~~~~~~~~
postmen.cpp:73:17: warning: comparison between signed and unsigned integer expressions [-Wsign-compare]
             if(i==v[u].size()-1)vv=-1;
                ~^~~~~~~~~~~~~~~

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