public void solve() throws Exception {
P[] ps = new P[N];
Map<Integer, Set<Integer>> map = new HashMap<Integer, Set<Integer>>();
for (int i = 0; i < N; i++) {
P p = new P();
p.x = sc.nextInt();
p.y = sc.nextInt();
ps[i] = p;
if (!map.containsKey(p.x)) {
Set<Integer> set = new HashSet<Integer>();
map.put(p.x, set);
}
map.get(p.x).add(p.y);
}
Arrays.sort(
ps,
new Comparator<P>() {
@Override
public int compare(P p1, P p2) {
if (p1.x != p2.x) {
return p1.x - p2.x;
}
return p1.y - p2.y;
}
});
List<Pair> yp = new ArrayList<Pair>();
for (int i = 0; i < ps.length - 1; i++) {
if (ps[i].x != ps[i + 1].x) continue;
int lidx = i + 1;
while (lidx + 1 < ps.length && ps[i].x == ps[lidx + 1].x) {
lidx++;
}
Pair pair = new Pair();
pair.s = ps[i].y;
pair.l = ps[lidx].y;
pair.base = ps[i].x;
yp.add(pair);
i = lidx;
}
Arrays.sort(
ps,
new Comparator<P>() {
@Override
public int compare(P p1, P p2) {
if (p1.y != p2.y) {
return p1.y - p2.y;
}
return p1.x - p2.x;
}
});
List<Pair> xp = new ArrayList<Pair>();
for (int i = 0; i < ps.length - 1; i++) {
if (ps[i].y != ps[i + 1].y) continue;
int lidx = i + 1;
while (lidx + 1 < ps.length && ps[i].y == ps[lidx + 1].y) {
lidx++;
}
Pair pair = new Pair();
pair.s = ps[i].x;
pair.l = ps[lidx].x;
pair.base = ps[i].y;
xp.add(pair);
i = lidx;
}
int ans = 0;
for (int i = 0; i < yp.size(); i++) {
int xnow = yp.get(i).base;
int sy = yp.get(i).s;
int ly = yp.get(i).l;
for (int j = 0; j < xp.size(); j++) {
int y = xp.get(j).base;
if (y < sy || ly < y) continue;
if (xp.get(j).s > xnow || xp.get(j).l < xnow) continue;
try {
if (!map.get(xnow).contains(y)) {
ans++;
map.get(xnow).add(y);
}
} catch (Exception ex) {
}
}
}
ans += ps.length;
out.println(ans);
}
