Submission #765305

#	Time	Username	Problem	Language	Result	Execution time	Memory
765305		raysh07	Crocodile's Underground City (IOI11_crocodile)	C++17	89 / 100	435 ms	77128 KiB

crocodile

#include "crocodile.h"
#include <bits/stdc++.h>
using namespace std;
#define INF (int)(1e18 + 1)
#define int long long

int n, m;
const int maxn = 1e5 + 69;
vector <pair<int, int>> adj[maxn];
int dp[maxn][2];

int32_t travel_plan(int32_t N, int32_t M, int32_t R[][2], int32_t L[], int32_t K, int32_t P[])
{
	n = N, m = M;
	for (int i = 0; i < n; i++){
		dp[i][0] = dp[i][1] = INF;
	}

	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]});
	}

	for (int i = 0; i < K; i++){
		dp[P[i]][0] = dp[P[i]][1] = 0;
	}

	//dp[i][0] = best path, dp[i][1] = second best path, update only with help of second best path values 
	priority_queue <pair<int, int>> pq;
	for (int i = 0; i < n; i++){
		pq.push({-dp[i][1], i});
	}

	while (!pq.empty()){
		auto pi = pq.top();
		pq.pop();

		int d = -pi.first;
		int u = pi.second;

		if (d != dp[u][1]) continue;

		for (pair <int, int> pi : adj[u]){
			int v = pi.first;
			int w = pi.second;
			int val = d + w;

			if (val < dp[v][0]){
				dp[v][1] = dp[v][0];
				dp[v][0] = val;
				pq.push({-dp[v][1], v});
			} else if (val < dp[v][1]) {
				dp[v][1] = val;
				pq.push({-dp[v][1], v});
			}
		}
	}

	return (int32_t)dp[0][1];
}

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