void prog()
{
cin = new Scanner();
int N = cin.nextInt();
Pair[] box = new Pair[N];
for (int i = 0; i < N; i++)
{
box[i] = new Pair(cin.nextInt(), cin.nextInt());
}
Array.Sort <Pair>(box, (a, b) => (a.Key > b.Key ? 1 : (a.Key < b.Key ? -1 : (a.Value < b.Value ? 1 : (a.Value > b.Value ? -1 : 0)))));
SegTreeMax segtree = new SegTreeMax(100001);
int ans = 0;
for (int i = 0; i < N; i++)
{
int h = box[i].Value;
int now = segtree.getMax(0, h) + 1;
ans = Math.Max(ans, now);
segtree.add(h, now);
}
Console.WriteLine(ans);
}
public void Solve()
{
if (N == 1)
{
Console.WriteLine(0);
return;
}
for (int i = 0; i < N; i++)
{
Array.Sort(XY[i]);
}
Array.Sort(XY,
(a, b) => {
if (a[0] == b[0])
{
return(a[1].CompareTo(b[1]));
}
return(a[0].CompareTo(b[0]));
});
var minST = new SegTreeMin[2];
var maxST = new SegTreeMax[2];
for (int i = 0; i < 2; i++)
{
minST[i] = new SegTreeMin(N);
maxST[i] = new SegTreeMax(N);
for (int j = 0; j < N; j++)
{
minST[i].Update(j, XY[j][i]);
maxST[i].Update(j, XY[j][i]);
}
}
var SH = new SkewHeap <Pair>();
for (int i = 1; i < N; i++)
{
SH.Push(new Pair(i, XY[i][1]));
}
long ans = (maxST[0].Max - minST[0].Min) * (maxST[1].Max - minST[1].Min);
while (SH.Count > 0)
{
var p = SH.Top; SH.Pop();
int idx = p.Pos;
maxST[0].Update(idx, XY[idx][1]);
maxST[1].Update(idx, XY[idx][0]);
minST[0].Update(idx, XY[idx][1]);
minST[1].Update(idx, XY[idx][0]);
var v = (maxST[0].Max - minST[0].Min) * (maxST[1].Max - minST[1].Min);
ans = Math.Min(ans, v);
}
Console.WriteLine(ans);
}
