#include <iostream>
#include <cstdio>
#include <vector>
#include <map>

using namespace std;

#define forn(i, n) for(int i = 0; i < (int) (n); i++)
#define isIn(i, c) ((c).find(i) != (c).end())

const int SIZE = 110000;

map< pair<int, int>, int > ps;

vector<int> edges[SIZE];
vector<bool> visited(SIZE);

int N, M;

void dfs(int s){
    if(!visited[s]){
        visited[s] = true;
        forn(i, edges[s].size()) dfs(edges[s][i]);
    }
}

int main(){
#ifdef ACM
    freopen("test.in", "r", stdin);
#endif

    while(scanf("%d", &M) && M != -1){
        N = 0;
        ps.clear();

        forn(i, M){
            int x1, x2, y1, y2;
            scanf("%d %d %d %d", &x1, &y1, &x2, &y2);

            pair<int, int> p1(x1, y1), p2(x2, y2);

            if(!isIn(p1, ps)){
                edges[N].clear();
                ps.insert(make_pair(p1, N++));
            }

            if(!isIn(p2, ps)){
                edges[N].clear();
                ps.insert(make_pair(p2, N++));
            }

            edges[ ps[p1] ].push_back(ps[p2]);
            edges[ ps[p2] ].push_back(ps[p1]);
        }

        fill(visited.begin(), visited.end(), false);
        int C = 0;

        forn(i, N){
            if(!visited[i]) C++;
            dfs(i);
        }

        printf("%d\n", C + M - N);
    }

    return 0;
}