Submission #374331

#	Time	Username	Problem	Language	Result	Execution time	Memory
374331		topovik	Odašiljači (COCI20_odasiljaci)	C++14	70 / 70	264 ms	33356 KiB

odasiljaci

#include <bits/stdc++.h>
#define f first
#define s second
#define pb push_back

using namespace std;

typedef long long ll;
typedef long double ld;

const ll N = 1e6 + 100;
const ll oo = 1e9 + 7;

int pred[N], r[N];

ld dist(ld x, ld y, ld x1, ld y1)
{
    return sqrt(pow(x - x1, 2) + pow(y - y1, 2));
}

int cmp(int x)
{
    if (x == pred[x]) return x;
    else return pred[x] = cmp(pred[x]);
}

void unite(int x, int y)
{
    if (r[x] > r[y]) pred[y] = x;
    else
    {
        pred[x] = y;
        r[y] += (r[x] == r[y]);
    }
}

int main()
{
    int n;
    cin >> n;
    ld x[n], y[n];
    for (int i = 0; i < n; i++) cin >> x[i] >> y[i];
    vector <pair<ld, pair<int, int> > > qur;
    for (int i = 0; i < n; i++)
        for (int j = 0; j < n; j++)
            if (i != j) qur.pb({dist(x[i], y[i], x[j], y[j]), {i, j}});
    for (int i = 0; i < n; i++) pred[i] = i, r[i] = 0;
    sort(qur.begin(), qur.end());
    int cn = 0;
    cout << setprecision(7) << fixed;
    for (int i = 0; i < qur.size(); i++)
    {
        int x = qur[i].s.f, y = qur[i].s.s;
        if (cmp(x) != cmp(y))
        {
            cn++;
            unite(cmp(x), cmp(y));
            if (cn == n - 1)
            {
                cout << (qur[i].f / (ld)2) << endl;
                return 0;
            }
        }
    }
}

Compilation message (stderr)

odasiljaci.cpp: In function 'int main()':
odasiljaci.cpp:51:23: warning: comparison of integer expressions of different signedness: 'int' and 'std::vector<std::pair<long double, std::pair<int, int> > >::size_type' {aka 'long unsigned int'} [-Wsign-compare]
   51 |     for (int i = 0; i < qur.size(); i++)
      |                     ~~^~~~~~~~~~~~

• Subtask 1: 70 / 70