#include<bits/stdc++.h>
#define ll long long
using namespace std;
int main()
{
int t;
cin >> t;
while(t--)
{
int n;
cin >> n;
int right = 2, left = 2, mid = 3;
map<pair<ll, ll>, bool> mp;
for (int i = 0; i < n; i++){
ll r, c;
cin >> r >> c;
mp[{r, c}] = 1;
if (left && c < 0){
if (r == 1 && (mp[{2, c}] == 1 || mp[{2, c + 1}] == 1 || mp[{2, c - 1}] == 1)) left = 0;
else if (r == 2 && (mp[{1, c}] == 1 || mp[{1, c + 1}] == 1 || mp[{1, c - 1}] == 1)) left = 0;
else left = 1;
}
else if (right && c > 0){
if (r == 1 && (mp[{2, c}] == 1 || mp[{2, c + 1}] == 1 || mp[{2, c - 1}] == 1)) right = 0;
else if (r == 2 && (mp[{1, c}] == 1 || mp[{1, c + 1}] == 1 || mp[{1, c - 1}] == 1)) right = 0;
else right = 1;
}
if (r == 2 && c == 0){
right = min(right, 1);
left = min(left, 1);
}
}
if (mp[{1, 1}] == 1) mid--;
if (mp[{2, 0}] == 1) mid--;
if (mp[{1, -1}] == 1) mid--;
cout << min(mid, right + left) << endl;
}
}