Submission #824133

#	Time	Username	Problem	Language	Result	Execution time	Memory
824133		Moses	Road Closures (APIO21_roads)	C++14	0 / 100	630 ms	27484 KiB

roads

#include "roads.h"
#include <bits/stdc++.h>
#define F first
#define S second
using namespace std;
const int N = 1e5+7;
typedef pair<int,int> pii;
vector<int> g[N];
int deg[N];

std::vector<long long> minimum_closure_costs(int N, std::vector<int> U,
                                             std::vector<int> V,
                                             std::vector<int> W) {
	vector<long long> ans(N,0);
	int n = N;
	for(int i = 0 ; i < n-1 ; i++) {
		g[U[i]].push_back(V[i]);
		g[V[i]].push_back(U[i]);
		deg[U[i]]++;
		deg[V[i]]++;
	}
	
	set<pii> st;
	for(int i = 0 ; i < n ; i++) st.insert({-deg[i],i});
	int cnt = 0;
	for(int i = N-1 ; i >= 0 ; i--) {
		while(!st.empty() && -(*st.begin()).F > i) {
			auto x = *st.begin();
			st.erase(st.begin());
			cnt++;
			int u = x.S;
			
			pii mx = {-1,-1};
			sort(g[u].begin(),g[u].end(),[&](int x,int y) {return deg[x] < deg[y];});
			int v = g[u].back();
			g[u].pop_back();
			st.erase({-deg[v],v});
			//cerr << u << ' ' << v << '\n';
			
			sort(g[v].begin(),g[v].end(),[&](int x,int y) {return deg[x] < deg[y];});
			g[v].pop_back();
			deg[u]--;
			if (deg[u]) st.insert({-deg[u],u});
			deg[v]--;
			if (deg[v]) {
				st.insert({-deg[v],v});
			}
		}
		ans[i] = cnt;
	}
	return ans;
}

Compilation message (stderr)

roads.cpp: In function 'std::vector<long long int> minimum_closure_costs(int, std::vector<int>, std::vector<int>, std::vector<int>)':
roads.cpp:33:8: warning: variable 'mx' set but not used [-Wunused-but-set-variable]
   33 |    pii mx = {-1,-1};
      |        ^~

• Subtask 1: 0 / 5
• Subtask 2: 0 / 7
• Subtask 3: 0 / 14
• Subtask 4: 0 / 10
• Subtask 5: 0 / 17
• Subtask 6: 0 / 25
• Subtask 7: 0 / 22