#include <bits/stdc++.h>
using namespace std;
typedef long long ll;
int a[1000];
bool sorted(string str) {
for (int i = 1; i < str.size(); i++) {
if (str[i] < str[i-1]) return false;
}
return true;
}
void bfs(int n) {
map<string,string> prev;
map<string,pair<int,int>> move;
set<string> seen;
string str = "";
for (int i = 0; i < n; i++) str += to_string(a[i]);
prev[str] = "";
seen.insert(str);
vector<string> queue;
queue.push_back(str);
for (int i = 0; i < queue.size(); i++) {
str = queue[i];
if (sorted(str)) {
vector<pair<int,int>> v;
while (prev[str] != "") {
v.push_back(move[str]);
str = prev[str];
}
cout << v.size() << "\n";
for (int i = v.size()-1; i >= 0; i--) {
cout << v[i].first << " " << v[i].second << "\n";
}
return;
}
for (int j = 0; j < n; j++) {
for (int k = j+2; k < n; k++) {
string uusi = str;
swap(uusi[j],uusi[k]);
if (!seen.count(uusi)) {
seen.insert(uusi);
move[uusi] = {j+1,k+1};
prev[uusi] = str;
queue.push_back(uusi);
}
}
}
}
cout << -1 << "\n";
}
void testCase() {
int n;
cin >> n;
for (int i = 0; i < n; i++) cin >> a[i];
if (n < 5) {
bfs(n);
} else {
vector<pair<int,int>> v;
for (int i = 0; i < n; i++) {
if (a[i] == i+1) continue;
int ind = 0;
for (int j = 0; j < n; j++) {
if (a[j] == i+1) {
ind = j;
break;
}
}
if (ind == i+1) {
if (i >= 2) {
v.push_back({1,ind+1});
v.push_back({1,i+1});
v.push_back({1,ind+1});
} else {
v.push_back({n,ind+1});
v.push_back({n,i+1});
v.push_back({n,ind+1});
}
swap(a[ind],a[i]);
} else {
swap(a[ind],a[i]);
v.push_back({ind+1, i+1});
}
}
cout << v.size() << "\n";
for (int i = 0; i < v.size(); i++) {
cout << v[i].first << " " << v[i].second << "\n";
}
}
}
int main() {
ios_base::sync_with_stdio(0);
cin.tie(0);
int t;
cin >> t;
for (int i = 0; i < t; i++) {
testCase();
}
}
