#include <bits/stdc++.h>
#define init(x) memset (x,0,sizeof (x))
#define ll long long
#define ull unsigned long long
#define INF 0x3f3f3f3f
using namespace std;
const int MAX = 1e6 + 5;
const int MOD = 1e9 + 7;
inline int read ();
struct node
{
	int l,r;
} f[MAX];
int t,n,ok;
map <pair <int,int>,int> mp,vis;
bool cmp (node x,node y)
{
	if (x.l == y.l) return x.r < y.r;
	return x.l < y.l;
} 
int main ()
{
	//freopen (".in","r",stdin);
	//freopen (".out","w",stdout);
	srand (time (0));
	t = read ();
	while (t--)
	{
		n = read ();ok = 0;
		mp.clear ();vis.clear ();
		for (int i = 1;i <= n;++i) f[i].l = read (),f[i].r = read ();
		for (int i = 1;i <= n;++i)
		{
			if (mp[{f[i].l,f[i].r}]) {puts ("0");ok = 1;break;};
			mp[{f[i].l,f[i].r}] = 1; 
		}
		if (ok) continue;
		for (int i = 1;i <= min (500000,n * 100);++i)
		{
			int x = rand () % n + 1,y = rand () % n + 1;
			if (x == y) continue;
			if (f[x].r + 1 == f[y].l)
			{
				if (mp[{f[x].l,f[y].r}] && !vis[{x,y}]) {puts ("0");ok = 1;break;};
				mp[{f[x].l,f[y].r}] = 1;vis[{x,y}] = 1;
			}
			swap (x,y);
			if (f[x].r + 1 == f[y].l)
			{
				if (mp[{f[x].l,f[y].r}] && !vis[{x,y}]) {puts ("0");ok = 1;break;};
				mp[{f[x].l,f[y].r}] = 1;vis[{x,y}] = 1;
			}
		}
		if (!ok) puts ("1");
	}
	return 0;
}
inline int read ()
{
    int s = 0;int f = 1;
    char ch = getchar ();
    while ((ch < '0' || ch > '9') && ch != EOF)
	{
        if (ch == '-') f = -1;
        ch = getchar ();
    }
    while (ch >= '0' && ch <= '9')
	{
        s = s * 10 + ch - '0';
        ch = getchar ();
    }
    return s * f;
}