#include <stdio.h>

int	posters[10000][2];

int	total, utotal;

int	nums[20000];

int	unique(int);
int	search(int);

typedef struct _snode {
	short	who;
	short	a;
	short	b;
} node;

node	nodes[32800];//这个数字测试过的9999时，最大为32725

#define LEFT(x) (((x) + 1) * 2 - 1)
#define RIGHT(x) (((x) + 1) * 2)

void	create_tree(int, int, int);
void	free_tree(void);
void	place(int, int, int, int);

int	getresult(void);

int	comp(const void *, const void *);

int
main(int argc, char *argv[])
{
	int	n, i;
	node	*pn;

	scanf("%d", &n);

	while ( n-- > 0 )
	{
		scanf("%d", &total);

		for ( i = 0; i < total; ++i )
		{
			scanf("%d%d", &posters[i][0], &posters[i][1]);

			nums[2*i] = posters[i][0];
			nums[2*i+1] = posters[i][1];
		}

		qsort(nums, 2*total, sizeof(int), comp);

		utotal = unique(2*total);

		for ( i = 0; i < total; ++i )
		{
			posters[i][0] = search(posters[i][0]);
			posters[i][1] = search(posters[i][1]);
//			printf("%d %d\n", posters[i][0], posters[i][1]);
		}

		if ( utotal == 1 )
		{
			printf("1\n");
			continue;
		}

		free_tree();

	       	create_tree(0, 0, utotal - 1);

		for ( i = 0; i < total; ++i )
			place(0, i, posters[i][0], posters[i][1]);

		printf("%d\n", getresult());
	}
	return 0;
}

int
comp(const void *left, const void *right)
{
	return *(int*)left - *(int*)right;
}

void
create_tree(int ni, int a, int b)
{
	if ( ni < 0 || ni >= sizeof nodes / sizeof nodes[0] || b - a < 0 ) return;

	nodes[ni].a = a;
	nodes[ni].b = b;

	if ( b - a > 0 )
	{
		create_tree(LEFT(ni), a, (a+b)/2);
		create_tree(RIGHT(ni), (a+b)/2 + 1, b);
	}
}

void
free_tree(void)
{
	int	i;

	for ( i = 0; i < sizeof nodes / sizeof nodes[0]; ++i )
	{
		nodes[i].a = nodes[i].b = 0;
		nodes[i].who = -1;
	}
}

void
place(int ni, int who, int a, int b)
{
	int	tmp, mid;

	if ( ni < 0 || ni >= sizeof nodes / sizeof nodes[0] || a > b ) return;

	if ( nodes[ni].a > b || nodes[ni].b < a ) return;

	if ( nodes[ni].a >= a && nodes[ni].b <= b )
		nodes[ni].who = who;
	else if ( nodes[ni].b == nodes[ni].a )//leaf
		return;
	else if ( b <= (mid = (nodes[ni].a + nodes[ni].b) / 2) )
	{
		place(LEFT(ni), who, a, b);
		if ( nodes[ni].who != -1 )
		{
			tmp = nodes[ni].who;
			nodes[ni].who = -1;
			place(ni, tmp, b + 1, nodes[ni].b);
		}
	}
	else if ( a >= mid + 1 )
	{
		place(RIGHT(ni), who, a, b);
		if ( nodes[ni].who != -1 )
		{
			tmp = nodes[ni].who;
			nodes[ni].who = -1;
			place(ni, tmp, nodes[ni].a, a - 1);
		}
	}
	else
	{
		place(LEFT(ni), who, a, b);
		place(RIGHT(ni), who, a, b);
		if ( nodes[ni].who != -1 )
		{
			tmp = nodes[ni].who;
			nodes[ni].who = -1;
			place(ni, tmp, nodes[ni].a, a - 1);
			place(ni, tmp, b + 1, nodes[ni].b);
		}
	}
}

int
getresult(void)
{
	void	see(int);
	int	i, res;

	for ( i = 0; i < total; ++i )
		nums[i] = 0;

	see(0);

	for ( i = res = 0; i < total; ++i )
		res += nums[i];

	return res;
}

void
see(int ni)
{
	if ( ni < 0 || ni >= sizeof nodes / sizeof nodes[0] ) return;

	if ( nodes[ni].who != -1 )
		nums[nodes[ni].who] = 1;
	else if ( nodes[ni].b - nodes[ni].a > 0 )
	{
		see(LEFT(ni));
		see(RIGHT(ni));
	}
}

int
unique(int size)
{
	int	i, next;

	for ( i = next = 0; i < size; ++i, ++next)
	{
		while ( i + 1 < size && nums[i] == nums[i+1] ) ++i;

		if ( next != i ) nums[next] = nums[i];
	}

	return next;
}

int
search(int value)
{
	int	low, high, mid;

	low = 0;
	high = utotal - 1;

	while ( low <= high )
	{
		mid = (low + high) / 2;

		if ( nums[mid] == value )
			break;
		else if ( nums[mid] < value )
			low = mid + 1;
		else
			high = mid - 1;
	}

	return low <= high ? mid : -1;
}