1 #include<bits/stdc++.h>
2 #define ll long long
3 using namespace std;
4 const int N = 1e5 + 10;
5 struct node
6 {
7 ll t, x;
8 }a[N];
9
10 int main(){
11 ios::sync_with_stdio(0);cin.tie(0);cout.tie(0);
12 int t; cin >> t;
13 while(t--)
14 {
15 ll n; cin >> n;
16 for(int i = 1 ; i <= n ; i++){
17 cin >> a[i].t >> a[i].x;
18 }
19 ll res = 0, pos = 0;
20 ll id = 1, t = 0;
21 a[n + 1].t = 1000000000000000;
22
23 while(id <= n){
24 t = a[id].t;//当前时间
25 ll del = abs(pos - a[id].x);//运动到id位置需要的时间/位置差
26 if(del == 0){//不需要移动
27 res++;
28 id++;
29 continue;
30 }
31 ll tag = 0;//要运动的方向
32 if(a[id].x > pos){
33 tag = 1;//正
34 }else if(a[id].x < pos){
35 tag = -1;//负
36 }
37 while(id <= n && del && t + del > a[id].t){
38 ll dist = abs(pos - a[id].x);
39 if(dist <= del){
40 if((tag == 1 && a[id].x >= pos) || (tag == -1 && a[id].x <= pos)){
41 if(a[id + 1].t >= t + dist && a[id].t <= t + dist){
42 res++;
43 }
44 }
45 }
46 id++;
47 }
48 t += del;
49 pos += del * tag;
50 }
51 cout << res << endl;
52 }
53
54
55 return 0;
56 }
