Submission #53114915

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Source Code Expand

// #pragma GCC optimize("Ofast,unroll-loops")
#include<bits/stdc++.h>
using namespace std;
#define ll long long
#define inf (ll)1e18
#define pll pair<ll, ll>
#define vi vector<int>
#define vl vector<ll>
#define fi first
#define se second
#define lll __int128

const int N = 1e6 + 5;
ll fa[N];
ll find(ll x){
	if(fa[x] == x) return x;
	return fa[x] = find(fa[x]);
}
void merge(ll x, ll y){
	fa[find(x)] = find(y);
}
void solve() {
	ll n, m, k, c;
	cin >> n >> m;
	for (ll i = 1; i <= n; i++)
		fa[i] = i;
	vector<pair<ll, vl>> es;
	while (m--) {
		cin >> k >> c;
		vl t(k);
		for (ll i = 0; i < k; i++)
			cin >> t[i];
		es.push_back({c, t});
	}
	sort(es.begin(), es.end());
	ll ans = 0;
	for (auto [c, t] : es) {
		for (ll i = 1; i < t.size(); i++) {
			ll r1 = find(t[i - 1]), r2 = find(t[i]);
			if (r1 != r2) {
				// cout << t[i - 1] << " " << t[i] << endl;
				merge(t[i - 1], t[i]);
				ans += c;
			}
		}
	}
	set<ll> rs;
	for (ll i = 1; i <= n; i++) {
		rs.insert(find(i));
	}
	if (rs.size() != 1)
		cout << -1 << endl;
	else
		cout << ans << endl;
}

int main() {
	ios::sync_with_stdio(false);
  	cin.tie(0);
  	cout.tie(0);
	solve();
	return 0;
}

Submission Info

Compile Error

Main.cpp: In function ‘void solve()’:
Main.cpp:38:34: warning: comparison of integer expressions of different signedness: ‘long long int’ and ‘std::vector<long long int>::size_type’ {aka ‘long unsigned int’} [-Wsign-compare]
   38 |                 for (ll i = 1; i < t.size(); i++) {
      |                                ~~^~~~~~~~~~

Judge Result