public static void Run()
{
using (FastScanner fs = new FastScanner(new BufferedStream(Console.OpenStandardInput())))
using (StreamWriter writer = new StreamWriter(new BufferedStream(Console.OpenStandardOutput())))
{
int n = fs.NextInt();
Watchmen[] a = new Watchmen[n];
for (int i = 0; i < n; i++)
{
a[i] = new Watchmen { x = fs.NextInt(), y = fs.NextInt() };
}
a = a.OrderBy(w => w.x).ThenBy(w => w.y).ToArray();
Watchmen[] b = a.OrderBy(w => w.y).ToArray();
long ans = 0, sameX = 0, sameY = 0, dupNum = 0;
for (int i = 1; i < n; i++)
{
if (a[i].x == a[i - 1].x) sameX++;
else if (sameX != 0)
{
ans += (sameX * (sameX + 1)) / 2;
sameX = 0;
}
if (b[i].y == b[i - 1].y) sameY++;
else if (sameY != 0)
{
ans += (sameY * (sameY + 1)) / 2;
sameY = 0;
}
if (a[i].x == a[i - 1].x && a[i].y == a[i - 1].y) dupNum++;
else if (dupNum != 0)
{
ans -= (dupNum * (dupNum + 1)) / 2;
dupNum = 0;
}
}
if (sameX != 0)
{
ans += (sameX * (sameX + 1)) / 2;
sameX = 0;
}
if (sameY != 0)
{
ans += (sameY * (sameY + 1)) / 2;
sameY = 0;
}
if (dupNum != 0)
{
ans -= (dupNum * (dupNum + 1)) / 2;
dupNum = 0;
}
writer.WriteLine(ans);
}
}
public static void Run()
{
using (FastScanner fs = new FastScanner(new BufferedStream(Console.OpenStandardInput())))
using (StreamWriter writer = new StreamWriter(new BufferedStream(Console.OpenStandardOutput())))
{
int n = fs.NextInt();
Watchmen[] a = new Watchmen[n];
for (int i = 0; i < n; i++)
{
a[i] = new Watchmen {
x = fs.NextInt(), y = fs.NextInt()
};
}
a = a.OrderBy(w => w.x).ThenBy(w => w.y).ToArray();
Watchmen[] b = a.OrderBy(w => w.y).ToArray();
long ans = 0, sameX = 0, sameY = 0, dupNum = 0;
for (int i = 1; i < n; i++)
{
if (a[i].x == a[i - 1].x)
{
sameX++;
}
else if (sameX != 0)
{
ans += (sameX * (sameX + 1)) / 2;
sameX = 0;
}
if (b[i].y == b[i - 1].y)
{
sameY++;
}
else if (sameY != 0)
{
ans += (sameY * (sameY + 1)) / 2;
sameY = 0;
}
if (a[i].x == a[i - 1].x && a[i].y == a[i - 1].y)
{
dupNum++;
}
else if (dupNum != 0)
{
ans -= (dupNum * (dupNum + 1)) / 2;
dupNum = 0;
}
}
if (sameX != 0)
{
ans += (sameX * (sameX + 1)) / 2;
sameX = 0;
}
if (sameY != 0)
{
ans += (sameY * (sameY + 1)) / 2;
sameY = 0;
}
if (dupNum != 0)
{
ans -= (dupNum * (dupNum + 1)) / 2;
dupNum = 0;
}
writer.WriteLine(ans);
}
}
