Submission #582668

#	Time	Username	Problem	Language	Result	Execution time	Memory
582668		1ne	Crocodile's Underground City (IOI11_crocodile)	C++14	46 / 100	2 ms	468 KiB

crocodile

#include "crocodile.h"
#include <bits/stdc++.h>
using namespace std;
int travel_plan(int N, int M, int R[][2], int L[], int K, int P[])
{
	vector<vector<pair<int,int>>>adj(N);
	for (int i = 0;i<M;++i){
		adj[R[i][0]].push_back({R[i][1],L[i]});
		adj[R[i][1]].push_back({R[i][0],L[i]});
	}
	vector<bool>got(N,false);
	for (int i = 0;i<K;++i)got[P[i]] = true;
	vector<vector<long long>>dp(N,vector<long long>(2,1e9));
	vector<bool>visited(N,false),in_cycle(N,false);
	const long long maxn = 1e9;
	vector<int>parent(N,-1);
	function<long long(int)>dfs = [&](int u){
		if (got[u])return 0LL;
		if (visited[u]){
			int y = u;
			in_cycle[y] = true;
			y = parent[y];
			while(y!=u && y!=-1){
				in_cycle[y] = true;
				y = parent[y];
			}
			return dp[u][1];
		}
		if (in_cycle[u]){
			return dp[u][1];
		}
		visited[u] = true;
		for (auto x:adj[u]){
			if (x.first == parent[u])continue;
			parent[x.first] = u;
			long long temp = dfs(x.first) + x.second;
			parent[x.first] = -1;
			if (temp < dp[u][0]){
				dp[u][1] = dp[u][0];
				dp[u][0] = temp;
			}
			else if (temp < dp[u][1]){
				dp[u][1] = temp;
			}
		}
		visited[u] = false;
		return dp[u][1];
	};
	long long ans = dfs(0);
	return ans;
}

Compilation message (stderr)

crocodile.cpp: In function 'int travel_plan(int, int, int (*)[2], int*, int, int*)':
crocodile.cpp:15:18: warning: unused variable 'maxn' [-Wunused-variable]
   15 |  const long long maxn = 1e9;
      |                  ^~~~

• Subtask 1: 46 / 46
• Subtask 2: 0 / 43
• Subtask 3: 0 / 11