Submission #997179

#	Time	Username	Problem	Language	Result	Execution time	Memory
997179		mkola	Senior Postmen (BOI14_postmen)	C++14	100 / 100	279 ms	69804 KiB

postmen

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

#define pb push_back
#define sz size
#define all(x) begin(x), end(x)

#define ll long long

#define INF 1e18
#define MOD (int)(1e9 + 7)

int N, M, cnt[500005];
vector<pair<int, int>> adj[500005];
vector<int> cycle;
vector<vector<int>> ans; 

bool seen[500005];

void dfs(int v) {
	while(adj[v].sz()) {
		pair<int, int> p = adj[v].back();
		adj[v].pop_back();
		int u = p.first, id = p.second;
		if(!seen[id]) {
			seen[id] = true;
			dfs(u);
		}
	}
	cycle.pb(v);
}

int main() {
	ios_base::sync_with_stdio(0); cin.tie(0);
	cin >> N >> M;
	for(int i = 0; i < M; ++i) {
		int a, b;
		cin >> a >> b;
		adj[a].pb({b, i});
		adj[b].pb({a, i});
	}
	dfs(1);
	// 1 5 8 10 9 2 3 6 7 8 4 7 5 4 3 1
	stack<int> st;
	for(int i = 0; i < (int)cycle.sz(); ++i) {
		int v = cycle[i];
		cnt[v]++;
		if(cnt[v] > 1) {
			vector<int> cyc;
			while(st.top() != v) {
				cyc.pb(st.top());
				cnt[st.top()]--;
				st.pop();
			}
			st.pop();
			cnt[v]--;
			cyc.pb(v);
			ans.pb(cyc);
		}
		st.push(v);
	}
	for(auto const &p : ans) {
		for(int v : p)
			cout << v << ' ';
		cout << '\n';
	}
	return 0;
}

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