#include <cstdio>#include <cstring>#include <algorithm>#include <climits>#include <string>#include <iostream>#include <map>#include <cstdlib>#include <list>#include <set>#include <queue>#include <stack>#include<math.h>using namespace std;#define lson l,mid,rt<<1#define rson mid+1,r,rt<<1|1const int maxn = 44444;int color[maxn << 2];int vis[maxn];int q[maxn];int q1[maxn];int l[maxn];int r[maxn];int Hash[maxn];void down(int rt){    if (color[rt]){        color[rt << 1] = color[rt << 1 | 1] = color[rt];        color[rt] = 0;    }}void build(int l, int r, int rt){    color[rt] = 0;    if (l == r) return;    int mid = (l + r) >> 1;    build(lson);    build(rson);}void update(int L, int R, int add, int l, int r, int rt){    if (L <= l&&r <= R){        color[rt] = add; return;    }    down(rt);    int mid = (l + r) >> 1;    if (L <= mid) update(L, R, add, lson);    if (R>mid) update(L, R, add, rson);}void ask(int l, int r, int rt){    if (color[rt]){        Hash[color[rt]] = 1; return;    }    int mid = (l + r) >> 1;    ask(lson); ask(rson);}int erfen(int key, int a[], int len){    int l = 0; int r = len - 1;    while (l <= r){        int mid = (l + r) >> 1;        if (a[mid] == key) return mid + 1;        if (a[mid]<key) l = mid + 1;        if (a[mid]>key) r = mid - 1;    }}int cmp(const int &a, const int &b){    return a<b;}int main(){    int Icase, n;    int ans, ans1;    scanf("%d", &Icase);    while (Icase--){        ans = 0; ans1 = 0;        memset(Hash, 0, sizeof(Hash));        scanf("%d", &n);        for (int i = 0; i<n; i++){            scanf("%d%d", &l[i], &r[i]);            q[ans++] = l[i]; q[ans++] = r[i];        }        sort(q, q + ans, cmp);        memset(vis, 0, sizeof(vis));        for (int i = 0; i<ans - 1; i++){            if (q[i] == q[i + 1]) vis[i + 1] = 1;        }        int ans1 = 0;        for (int i = 0; i<ans; i++)        if (!vis[i]) q1[ans1++] = q[i];        for (int i = 0; i<n; i++){            l[i] = erfen(l[i], q1, ans1); r[i] = erfen(r[i], q1, ans1);        }        build(1, ans1, 1);        for (int i = 0; i<n; i++){            update(l[i], r[i], i + 1, 1, ans1, 1);        }        ask(1, ans1, 1);        int gg = 0;        for (int i = 1; i <= n; i++)        if (Hash[i]) gg++;        cout << gg << endl;    }    return 0;}