#define _CRT_SECURE_NO_WARNINGS
#include "bits/stdc++.h"
using namespace std;
#define all(a) a.begin(), a.end()
typedef long long ll;
typedef pair<ll, ll> pll;
typedef long double ld;
mt19937 rnd(std::chrono::high_resolution_clock::now().time_since_epoch().count());
signed main() {
#ifdef _DEBUG
    freopen("input.txt", "r", stdin);
    freopen("output.txt", "w", stdout);
#endif
    ios_base::sync_with_stdio(false);
    cin.tie(nullptr);
    ll t;
    cin >> t;
    while (t--) {
        ll n;
        cin >> n;
        vector<ll>a(n);
        for (ll i = 0; i < n; i++) {
            cin >> a[i];
        }
        vector<ll> b = a;
        reverse(all(b));
        ll sum = 0;
        for (ll i = 0; i < n; i++) {
            b[i] = b[i] - sum;
            sum += b[i];
        }
        reverse(all(b));
        deque<ll> last_level;
        cout << sum << '\n';
        for (ll i = 0; i < b.back(); i++) {
            last_level.push_back(i);
        }
        map<ll, ll> check;//проверка ответа
        deque<pair<ll, ll>> need_free;
        for (ll i = n - 1; i > 0; i--) {
            ll now = last_level.back() + 1;
            ll x = b[i - 1];
            ll cnt = 0;
            deque<ll> sub;
            bool is_free = false;
            while (x > 0) {
                if (cnt == i) {
                    if (last_level.size() > 1) {
                        cnt = 0;
                        last_level.pop_front();
                    }
                    else {
                        is_free = true;
                    }
                }
                if (is_free) {
                    if (!need_free.empty()) {
                        need_free.back().second--;
                        cout << need_free.back().first << ' ' << now << '\n';
                        check[need_free.back().first]++;
                        sub.push_back(now++);
                        cnt++;
                        x--;
                        if (need_free.back().second == 0 && need_free.size() > 1) {
                            need_free.pop_back();
                        }
                    }
                }
                else {
                    cout << last_level.front() << ' ' << now << '\n';
                    check[last_level.front()]++;
                    cnt++;
                    sub.push_back(now++);
                    x--;
                }
            }
            if (cnt < i) {
                need_free.push_back({ last_level.front(), i - cnt });
                last_level.pop_front();
                while (!last_level.empty()) {
                    need_free.push_back({ last_level.front(),i });
                    last_level.pop_front();
                }

            }
            last_level = sub;
        }
        //dec это массив востонавливается по исходящим степеням вершин дерева
        vector<ll> dec(n);
        for (ll i = 0; i < n; i++) {
            for (ll j = 0; j < sum; j++) {
                if (i <= check[j]) {
                    dec[i]++;
                }
            }
        }
        for (ll i = 0; i < dec.size(); i++) {
            cout << dec[i] << ' ';
        }
        cout << '\n';
    }
}