#include <bits/stdc++.h>
using namespace std;
int main() {
int t;
cin>>t;
while (t--) {
int n;
cin >> n;
set<int>s;
vector<int>st1;
vector<int>st2;
int a[n];
/// scan
for (int i = 0; i < n; i++) {
cin>>a[i];
s.insert(a[i]);
}
/// push to vector st1
for(auto t: s) st1.push_back(t);
int ans1=1;
int c1=0,c2=0;
/// set 1
for (int i = 0; i < st1.size()-1; ++i)
{
if(abs(st1[i]-st1[i+1])!=1) { ans1++;}
}
///set 2
for (int i = 0; i < n; ++i)
{
if(s.find(a[i])!=s.end()) {s.erase(s.find(a[i]));}
else st2.push_back(a[i]);
}
int ans2;
if(!st2.empty()) {
ans2=1;
sort(st2.begin(), st2.end());
for (int i = 0; i < st2.size() - 1; ++i) {
if(abs(st2[i]-st2[i+1])!=1) {ans2++; }
}
}
else ans2=0;
cout<<ans1+ans2<<endl;
}
return 0;
}
I2luY2x1ZGUgPGJpdHMvc3RkYysrLmg+CnVzaW5nIG5hbWVzcGFjZSBzdGQ7CmludCBtYWluKCkgewoKICAgIGludCB0OwogICAgY2luPj50OwoKICAgIHdoaWxlICh0LS0pIHsKICAgICAgICBpbnQgbjsKICAgICAgICBjaW4gPj4gbjsKICAgICAgICBzZXQ8aW50PnM7CiAgICAgICAgdmVjdG9yPGludD5zdDE7CiAgICAgICAgdmVjdG9yPGludD5zdDI7CiAgICAgICAgaW50IGFbbl07CiAgICAgICAgLy8vIHNjYW4KICAgICAgICBmb3IgKGludCBpID0gMDsgaSA8IG47IGkrKykgewogICAgICAgICAgICBjaW4+PmFbaV07CiAgICAgICAgICAgIHMuaW5zZXJ0KGFbaV0pOwogICAgICAgIH0KICAgICAgICAvLy8gcHVzaCB0byB2ZWN0b3Igc3QxCiAgICAgICAgZm9yKGF1dG8gdDogcykgc3QxLnB1c2hfYmFjayh0KTsKCgogICAgICAgIGludCBhbnMxPTE7IAogICAgICAgIGludCBjMT0wLGMyPTA7CiAgICAgICAgLy8vIHNldCAxCiAgICAgICAgZm9yIChpbnQgaSA9IDA7IGkgPCBzdDEuc2l6ZSgpLTE7ICsraSkKICAgICAgICB7CiAgICAgICAgICAgIGlmKGFicyhzdDFbaV0tc3QxW2krMV0pIT0xKSB7IGFuczErKzt9CgoKICAgICAgICB9CiAgICAgICAgCiAgICAgICAgLy8vc2V0IDIKCiAgICAgICAgZm9yIChpbnQgaSA9IDA7IGkgPCBuOyArK2kpCiAgICAgICAgewogICAgICAgICAgICBpZihzLmZpbmQoYVtpXSkhPXMuZW5kKCkpICB7cy5lcmFzZShzLmZpbmQoYVtpXSkpO30KICAgICAgICAgICAgZWxzZSBzdDIucHVzaF9iYWNrKGFbaV0pOwogICAgICAgIH0KICAgICAgICBpbnQgYW5zMjsKICAgICAgICBpZighc3QyLmVtcHR5KCkpIHsKICAgICAgICAgICAgYW5zMj0xOwoKICAgICAgICAgICAgc29ydChzdDIuYmVnaW4oKSwgc3QyLmVuZCgpKTsKICAgICAgICAgICAgCiAgICAgICAgICAgIAogICAgICAgICAgICBmb3IgKGludCBpID0gMDsgaSA8IHN0Mi5zaXplKCkgLSAxOyArK2kpIHsKCiAgICAgICAgICAgICAgICBpZihhYnMoc3QyW2ldLXN0MltpKzFdKSE9MSkge2FuczIrKzsgfQoKCgogICAgICAgICAgICB9CgogICAgICAgIH0KICAgICAgICBlbHNlIGFuczI9MDsKICAgICAgICAKICAgICAgICAKICAgICAgICAKICAgICAgICBjb3V0PDxhbnMxK2FuczI8PGVuZGw7CgoKCgoKICAgIH0KICAgIHJldHVybiAwOwp9
MTAKNgoyIDIgMyA0IDMgMQo1CjExIDggNyAxMCA5CjYKMTAwMDAwMDAwMCAxMDAwMDAwMDAwIDEwMDAwMDAwMDAgMTAwMDAwMDAwMCAxMDAwMDAwMDAwIDEwMDAwMDAwMDAKOAoxIDEgNCA0IDIgMyAyIDMKNgoxIDIgMyAyIDMgNAo3CjEwIDExIDExIDEyIDEyIDEzIDEzCjcKOCA4IDkgOSAxMCAxMCAxMQo4CjQgMTQgNSAxNSA2IDE2IDcgMTcKOAo1IDE1IDYgMTQgOCAxMiA5IDExCjUKNCAyIDIgMyA0Cg==
10
6
2 2 3 4 3 1
5
11 8 7 10 9
6
1000000000 1000000000 1000000000 1000000000 1000000000 1000000000
8
1 1 4 4 2 3 2 3
6
1 2 3 2 3 4
7
10 11 11 12 12 13 13
7
8 8 9 9 10 10 11
8
4 14 5 15 6 16 7 17
8
5 15 6 14 8 12 9 11
5
4 2 2 3 4