Submission #1091626

#	Time	Username	Problem	Language	Result	Execution time	Memory
1091626		raphaelp	Sightseeing (NOI14_sightseeing)	C++14	15 / 25	2289 ms	122360 KiB

sightseeing

#include <bits/stdc++.h>
using namespace std;
class UnionFind
{
private:
    vector<int> p;

public:
    UnionFind(int x)
    {
        p.assign(x, 0);
        for (int i = 0; i < x; i++)
            p[i] = i;
    }
    int find(int x) { return (p[x] == x) ? x : p[x] = find(p[x]); }
    bool merge(int a, int b)
    {
        int x = find(a), y = find(b);
        if (x == y)
            return 0;
        p[x] = y;
        return 1;
    }
};
void dfs(int x, int p, vector<vector<pair<int, int>>> &AR, vector<int> &dist, int cur)
{
    dist[x] = cur;
    for (int i = 0; i < AR[x].size(); i++)
    {
        if (AR[x][i].first == p)
            continue;
        dfs(AR[x][i].first, x, AR, dist, min(cur, AR[x][i].second));
    }
}
int main()
{
    int N, M, Q;
    cin >> N >> M >> Q;
    vector<vector<int>> AR;
    vector<vector<pair<int, int>>> buckets(100010);
    for (int i = 0; i < M; i++)
    {
        int a, b, c;
        cin >> a >> b >> c;
        a--, b--;
        buckets[c].push_back({a, b});
    }
    UnionFind UF(N);
    vector<vector<pair<int, int>>> AR2(N);
    for (int i = 100000; i >= 0; i--)
    {
        for (int j = 0; j < buckets[i].size(); j++)
        {
            if (UF.merge(buckets[i][j].first, buckets[i][j].second))
            {
                AR2[buckets[i][j].first].push_back({buckets[i][j].second, i});
                AR2[buckets[i][j].second].push_back({buckets[i][j].first, i});
            }
        }
    }
    vector<int> dist(N);
    dfs(0, 0, AR2, dist, 1000000);
    for (int i = 0; i < Q; i++)
    {
        int x;
        cin >> x;
        cout << dist[x - 1] << '\n';
    }
}

Compilation message (stderr)

sightseeing.cpp: In function 'void dfs(int, int, std::vector<std::vector<std::pair<int, int> > >&, std::vector<int>&, int)':
sightseeing.cpp:28:23: warning: comparison of integer expressions of different signedness: 'int' and 'std::vector<std::pair<int, int> >::size_type' {aka 'long unsigned int'} [-Wsign-compare]
   28 |     for (int i = 0; i < AR[x].size(); i++)
      |                     ~~^~~~~~~~~~~~~~
sightseeing.cpp: In function 'int main()':
sightseeing.cpp:52:27: warning: comparison of integer expressions of different signedness: 'int' and 'std::vector<std::pair<int, int> >::size_type' {aka 'long unsigned int'} [-Wsign-compare]
   52 |         for (int j = 0; j < buckets[i].size(); j++)
      |                         ~~^~~~~~~~~~~~~~~~~~~

• Subtask 1: 4 / 4
• Subtask 2: 5 / 5
• Subtask 3: 6 / 6
• Subtask 4: 0 / 10