Submission #1119671

#	Time	Username	Problem	Language	Result	Execution time	Memory
1119671		sasde	Senior Postmen (BOI14_postmen)	C++17	100 / 100	496 ms	69496 KiB

postmen

#include<bits/stdc++.h>

#define str string
#define task "strdel" 
#define ii pair<int,int>
#define iii pair<int,ii>
#define iv pair<ii,ii>
#define se second
#define fi first
#define ffi fi.fi
#define sfi se.fi
#define sse se.se
#define fse fi.se
#define lt(i, c, d) for(int i = c; i <= d; ++i)
#define fl(i, c, d) for(int i = d; i >= c; --i)
#define pb push_back
#define emb emplace_back
#define em emplace
using namespace std;
const int N=1e6+5,lg=20,mod=998244353;
mt19937 rd(chrono::steady_clock::now().time_since_epoch().count());
int Rand(int u,int v){
 return u+rd()%(v-u+1);
}
int n,m;
vector<ii>a[N];
bool k[N],k1[N];
list<int> eul(int u){
	list<int> ans={u};
	while(!a[u].empty()){
		k1[u]=true;
        int v=a[u].back().fi;
        int i=a[u].back().se;
        a[u].pop_back();
        if(k[i])continue;
        k[i]=true;
        u=v;
        ans.emb(u);
	}
	for(auto it=++ans.begin();it!=ans.end();++it){
		auto t=eul(*it);
		t.pop_back();
		// cout <<*it<<" "<<t.size()<<'\n';
		ans.splice(it,t);
		// ans.insert(it,t.begin(), 	t.end());
	}
 return ans;
}
bool h[N];
void solve(){
    cin >> n >> m;
    for(int i=1;i<=m;++i){
    	int u,v;
    	cin >> u >> v;
    	a[u].emb(v,i);
    	a[v].emb(u,i);
    }
    // for(int i:res)cout<<i<<" ";cout<<'\n';
    for(int i=1;i<=n;++i)
    	if(!k1[i]){
   
     list<int>res=eul(i);

    stack<int>s;
    for(int i:res){
       if(h[i]){
       	while(!s.empty()&&h[i]){
       		h[s.top()]=false;
            cout <<s.top()<<" ";
       		s.pop();
       	}
       	cout<<'\n';
       }
       h[i]=true;
       s.push(i);
    }

    }
    // cout <<1;

}
main()
{
	srand(time(0));
    ios_base::sync_with_stdio(false);
    cin.tie(NULL);
    cout.tie(NULL);
    if(fopen(task".inp","r")){
      freopen(task".inp","r",stdin);
      freopen(task".out","w",stdout);
    }
    int t=1;
   // cin >> t;
while(t--){
    solve();
    // cout<<'\n';
}

}

Compilation message (stderr)

postmen.cpp:82:1: warning: ISO C++ forbids declaration of 'main' with no type [-Wreturn-type]
   82 | main()
      | ^~~~
postmen.cpp: In function 'int main()':
postmen.cpp:89:14: warning: ignoring return value of 'FILE* freopen(const char*, const char*, FILE*)' declared with attribute 'warn_unused_result' [-Wunused-result]
   89 |       freopen(task".inp","r",stdin);
      |       ~~~~~~~^~~~~~~~~~~~~~~~~~~~~~
postmen.cpp:90:14: warning: ignoring return value of 'FILE* freopen(const char*, const char*, FILE*)' declared with attribute 'warn_unused_result' [-Wunused-result]
   90 |       freopen(task".out","w",stdout);
      |       ~~~~~~~^~~~~~~~~~~~~~~~~~~~~~~

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