Submission #1114785

#	Time	Username	Problem	Language	Result	Execution time	Memory
1114785		sosuke	악어의 지하 도시 (IOI11_crocodile)	C++14	100 / 100	335 ms	62620 KiB

crocodile

#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<array<int, 2>>> 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]});
	}

	// we use 1e9 instead of INT_MAX to prevent overflow
	const array<int, 2> DEF = {(int)1e9, (int)1e9};
	vector<array<int, 2>> dist(n, DEF);
	priority_queue<array<int, 2>> pq;
	for (int i = 0; i < k; i++) {
		pq.push({0, p[i]});
		dist[p[i]] = {0, 0};
	}

	while (!pq.empty()) {
		auto [time, at] = pq.top();
		pq.pop();
		time *= -1;  // undoing the negative number trick
		if (dist[at][1] < time) { continue; }
		for (const auto [nxt, weight] : adj[at]) {
			if (time + weight < dist[nxt][0]) {
				if (dist[nxt][0] < dist[nxt][1]) { pq.push({-dist[nxt][0], nxt}); }
				dist[nxt][1] = dist[nxt][0];
				dist[nxt][0] = time + weight;
			} else if (time + weight < dist[nxt][1]) {
				dist[nxt][1] = time + weight;
				pq.push({-dist[nxt][1], nxt});
			}
		}
	}
	return dist[0][1];
}

Compilation message (stderr)

crocodile.cpp: In function 'int travel_plan(int, int, int (*)[2], int*, int, int*)':
crocodile.cpp:21:8: warning: structured bindings only available with '-std=c++17' or '-std=gnu++17'
   21 |   auto [time, at] = pq.top();
      |        ^
crocodile.cpp:25:19: warning: structured bindings only available with '-std=c++17' or '-std=gnu++17'
   25 |   for (const auto [nxt, weight] : adj[at]) {
      |                   ^

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