Submission #1017047

# Submission time Handle Problem Language Result Execution time Memory
1017047 2024-07-08T19:15:08 Z Kodik Crocodile's Underground City (IOI11_crocodile) C++17
100 / 100
293 ms 66112 KB
#include <bits/stdc++.h>
using namespace std;
using ll = long long;
using pii = pair<int, int>;
using pll = pair<ll, ll>;
#define all(x) begin(x), end(x)
#define sz(x) (int) (x).size()
#define smin(a, b) a = min(a, b)
#define smax(a, b) a = max(a, b)
#define pb push_back
#define ins insert
#define f first 
#define s second 

int travel_plan(int N, int M, int R[][2], 
    int L[], int k, int p[]) {
    const ll INF = 1e18;
    int n = N, m = M;
    vector<vector<pii>> adj(n);
    for (int i = 0; i < m; i++) {
        int x = R[i][0], y = R[i][1],
            w = L[i];
        adj[x].pb({y, w});
        adj[y].pb({x, w});
    }
    vector<vector<ll>> dist(2, 
        vector<ll>(n, INF));
    priority_queue<pll> pq;
    for (int i = 0; i < k; i++) {
        pq.push({0, p[i]});
        dist[0][p[i]] = 0;
        dist[1][p[i]] = 0;
    }
    while (!pq.empty()) {
        auto N = pq.top(); pq.pop();
        ll u = N.s, t = -N.f;
        if (dist[1][u] != t) {
            continue;
        }
        for (auto [v, w] : adj[u]) {
            if (t + w < dist[0][v]) {
                if (dist[0][v] != dist[1][v]) {
                    pq.push({-dist[0][v], v});
                }
                swap(dist[0][v], dist[1][v]);
                dist[0][v] = t + w;
            } else if (t + w < dist[1][v]) {
                dist[1][v] = t + w;
                pq.push({-dist[1][v], v});
            }
        }
    }
    return (int) dist[1][0];
}
/**
 * Problem: IOI 2011 - Crocodile.
 * Observations:
 * 1. You will never go backwards.
 * 2. Worst case, you always take the
 * second best route forward, because
 * the crocodile will block the best
 * route possible.
 * 
 * Run Dijkstra from each escape, 
 * basing each distance off the second
 * best possibility for each node.
*/
# Verdict Execution time Memory Grader output
1 Correct 1 ms 4444 KB Output is correct
2 Correct 1 ms 4540 KB Output is correct
3 Correct 1 ms 4444 KB Output is correct
4 Correct 1 ms 4444 KB Output is correct
5 Correct 1 ms 4444 KB Output is correct
6 Correct 1 ms 4444 KB Output is correct
7 Correct 2 ms 4552 KB Output is correct
8 Correct 1 ms 4444 KB Output is correct
# Verdict Execution time Memory Grader output
1 Correct 1 ms 4444 KB Output is correct
2 Correct 1 ms 4540 KB Output is correct
3 Correct 1 ms 4444 KB Output is correct
4 Correct 1 ms 4444 KB Output is correct
5 Correct 1 ms 4444 KB Output is correct
6 Correct 1 ms 4444 KB Output is correct
7 Correct 2 ms 4552 KB Output is correct
8 Correct 1 ms 4444 KB Output is correct
9 Correct 2 ms 4696 KB Output is correct
10 Correct 1 ms 4444 KB Output is correct
11 Correct 1 ms 4444 KB Output is correct
12 Correct 3 ms 5060 KB Output is correct
13 Correct 2 ms 4956 KB Output is correct
14 Correct 1 ms 4444 KB Output is correct
15 Correct 1 ms 4444 KB Output is correct
# Verdict Execution time Memory Grader output
1 Correct 1 ms 4444 KB Output is correct
2 Correct 1 ms 4540 KB Output is correct
3 Correct 1 ms 4444 KB Output is correct
4 Correct 1 ms 4444 KB Output is correct
5 Correct 1 ms 4444 KB Output is correct
6 Correct 1 ms 4444 KB Output is correct
7 Correct 2 ms 4552 KB Output is correct
8 Correct 1 ms 4444 KB Output is correct
9 Correct 2 ms 4696 KB Output is correct
10 Correct 1 ms 4444 KB Output is correct
11 Correct 1 ms 4444 KB Output is correct
12 Correct 3 ms 5060 KB Output is correct
13 Correct 2 ms 4956 KB Output is correct
14 Correct 1 ms 4444 KB Output is correct
15 Correct 1 ms 4444 KB Output is correct
16 Correct 239 ms 57860 KB Output is correct
17 Correct 44 ms 16980 KB Output is correct
18 Correct 58 ms 18356 KB Output is correct
19 Correct 293 ms 66112 KB Output is correct
20 Correct 161 ms 47956 KB Output is correct
21 Correct 22 ms 9560 KB Output is correct
22 Correct 183 ms 46516 KB Output is correct