#include<bits/stdc++.h>

using namespace std;

vector<vector<int>> g;
vector<int> color;

void dfs(int cur, vector<bool> &used, int c)
{
    used[cur] = true;
    color[cur] = c;
    for(auto i : g[cur])
        if(!used[i])
            dfs(i, used, c);
}

main()
{
    int n, m, min_i = 1;
    cin >> n >> m;
    vector<pair<int, int>> a(n);
    g.resize(n + 1, vector<int> ());
    color.resize(n + 1);
    vector<int> v;
    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;
        g[f].push_back(t);
        g[t].push_back(f);
    }

    sort(a.begin(), a.end());
    vector<bool> used(n + 1, false);
    int c = 0;
    for(int i = 1; i <= n; i++)
    {
        vector<int> v;
        if(!used[i])
        {
            dfs(i, used, c);
            c++;
        }
    }

    vector<bool> used_color(n + 1, false);
    used_color[color[min_i]] = true;
    vector<pair<int, int>> ans;
    for(auto i : a)
    {
        if(!used_color[color[i.second]])
        {
            ans.push_back({i.second, min_i});
            used_color[color[i.second]] = true;
        }
    }

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