Submission #393087

#	Time	Username	Problem	Language	Result	Execution time	Memory
393087		abdzag	Connecting Supertrees (IOI20_supertrees)	C++17	Compilation error	0 ms	0 KiB

supertrees

#include<bits/stdc++.h>
#define rep(i,a,b) for(int i=a;i<int(b);i++)
#define rrep(i,a,b)for(int i=a;i>int(b);i--)
#define all(v) v.begin(),v.end()
#define trav(a,v) for(auto& a: v)
typedef long long ll;
using namespace std;
const long long inf = 1e15;

vector<ll> p(2001);
vector<ll> Rank(2001);
ll Ufindset(ll i) {
	if (p[i] == i)return i;
	return p[i] = Ufindset(p[i]);
}
void UjoinSet(ll i, ll j) {
	ll si = Ufindset(i);
	ll sj = Ufindset(j);
	if (sj == si)return;
	if ( Rank[sj]> Rank[si])swap(sj, si);
	p[sj] = si;
	if (Rank[sj] == Rank[si]) Rank[si]++;
}

int constrct(vector<vector<int>> v) {
	rep(i, 0, 2001)p[i] = i;
	rep(i, 0, v.size()) {
		rep(j, 0, v.size()) {
			if (v[i][j]) UjoinSet(i, j);
		}
	}
	vector<vector<int>> b(v.size(), vector<int>(v.size()));
	rep(i, 0, v.size()) {
		if (p[i] != i) {
			b[i][p[i]]=1;
			b[p[i]][i] = 1;
		}
	}
	vector<vector<int>> check(v.size(), vector<int>(v.size()));
	rep(i, 0, v.size()) {
		vector<int> curvec(v.size());
		queue<ll> q;
		q.push(i);
		while (!q.empty()) {
			ll cur = q.front();
			curvec[cur] = 1;
			trav(a, b[cur])if (!curvec[a])q.push(a);
		}
		check[i] = curvec;
	}
	if (b != check)return 0;
	build(b);
	return 1;
}

Compilation message (stderr)

supertrees.cpp: In function 'int constrct(std::vector<std::vector<int> >)':
supertrees.cpp:52:2: error: 'build' was not declared in this scope
   52 |  build(b);
      |  ^~~~~