#include<bits/stdc++.h>

using namespace std;

vector<int> p, _size;

int find(int v)
{
    if(p[v] == v)
        return v;
    return p[v] = find(p[v]);
}

bool union_s(int a, int b)
{
    a = find(a);
    b = find(b);
    if (a != b)
    {
        if (_size[a] < _size[b])
            swap(a, b);
        p[b] = a;
        _size[a] += _size[b];
        return true;
    }
    else
        return false;
}

main()
{
    int n, m, min_i = 1;
    cin >> n >> m;
    vector<pair<int, int>> a(n);
    p.resize(n + 1);
    for(int i = 1; i <= n; i++)
        p[i] = i;
    _size.resize(n + 1, 0);
    for(int i = 0; i < n; i++)
    {
        cin >> a[i].first;
        if(a[i] < a[min_i - 1])
            min_i = i + 1;
        a[i].second = i + 1;
    }
    for(int i = 0; i < m; i++)
    {
        int f, t;
        cin >> f >> t;
        union_s(f, t);
    }
    sort(a.begin(), a.end());
    vector<pair<int, int>> ans;
    for(auto i : a)
        if(union_s(i.second, min_i))
            ans.push_back({i.second, min_i});

    cout << ans.size() << "\n";
    for(auto i : ans)
        cout << i.first << " " << i.second << "\n";
}