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#include <bits/stdc++.h>
using namespace std;

typedef long long LL;
typedef long double LD;
typedef pair < int, int > PII;
typedef pair < LL, LL > PLL;
typedef pair < LD, LD > PDD;

#define _upgrade ios_base::sync_with_stdio(0); cin.tie(0); cout.tie(0);
#define all(x) (x).begin(), (x).end()
#define sz(x) (int)(x).size()
template < typename _T > inline void _DBG(const char *s, _T x) { cerr << s << " = " << x << "\n"; }
template < typename _T, typename... args > void _DBG(const char *s, _T x, args... a) { while(*s != ',') cerr << *s++; cerr << " = " << x << ','; _DBG(s + 1, a...); }

#ifdef LOCAL
#define DBG(...) _DBG(#__VA_ARGS__, __VA_ARGS__)
#define __gcd gcd
#else
#define DBG(...) (__VA_ARGS__)
#define cerr if(0) cout
#endif

// ********************** CODE ********************** //

int n, leaves = 0;

int main()
{
    _upgrade
    cin >> n;
    for(int i = 1; i <= n; i++)
    {
        int x; cin >> x;
        if(x == 1)
            leaves++;
    }
    if(leaves >= 2)
    {
        cout << 0 << "\n";
        cout << 2 << "\n";
        cout << "1 2" << "\n";
    }
    else if(leaves == 1)
    {
        cout << 1 << "\n";
        cout << 2 << "\n";
        cout << "1 2" << "\n";
    }
    else
    {
        cout << 2 << "\n";
        cout << 2 << "\n";
        cout << "1 2" << "\n";
    }
	return 0;
}