// template.cpp
// add use inp.txt for file input
/*
Pragma:
If ever in doubt about whether your pragmas are correct,
turn on most compiler warnings with the command-line option -Wall(or the more specific -Wunknown-pragmas). 
use assert(__builtin_cpu_supports("avx2")) to check if intruction set is available
*/

// #pragma GCC optimize("O3","unroll-loops")
#pragma GCC optimize ("Ofast")
#pragma GCC target("avx2,bmi,bmi2,popcnt,lzcnt")
// #pragma GCC target("sse4") // instead of avx2
// __attribute__((target("avx2"), optimize("O3", "unroll-loops")))

#include <bits/stdc++.h>

#define oo (1000'000'000'000'000'000LL)
#define cif(i, n) for(int i = 0; i < n; i++)
#define ccif(i, l, r) for(int i = l; i < r; i++)
#define rif(i, n) for(int i = n-1; i >= 0; i--)
#define scan(a, __n) {for(int __ = 0; __ < __n; __++)cin >> a[__];}
#define print(a, __n) {for(int __ = 0; __ < __n; __++)cout << a[__] << ' '; cout << '\n';}
#define sz(s) ((int)s.size())
#define dbg(x) cerr << #x << " : " << x << endl;
// #define mset(a, chr) memset(a, chr, sizeof a)
#define mset(a) memset(a, 0, sizeof a)
//  #define int ll

#define fastIO ios::sync_with_stdio(false), cin.tie(NULL), cout.tie(NULL);

#define ff first
#define ss second

#define all(v) v.begin(), v.end()
#define uni(v) sort(all(v)), v.resize(unique(all(v))-v.begin());

// #define c0 (v<<1)
// #define c1 (c0|1)
// #define md ((l+r)/2)

using namespace std;

typedef unsigned long long ull;
typedef long long ll;
typedef double ld;
typedef pair<int, int> pii;
typedef pair<ll, ll> pll;
typedef vector<int> vi;
typedef vector<ll> vl;
typedef vector<pii> vii;
typedef vector<pll> vll;
typedef vector<ld> vd;
typedef pair<ld, ld> pt;
typedef vector<pt> vpt;



const int mod = 1e9+7;

// const string fileName = "";

// const int maxFac = 1e6+7; 
// ll fac[maxFac], _fac[maxFac];

// ll po(ll b, ll p){
//     b %= mod;
//     p %= mod-1;
//     ll r = 1;
//     while(p){
//         if(p&1)r = r*b%mod;
//         p >>= 1;
//         b = b*b%mod;
//     }
//     return r;
// }

// ll choose(ll k, ll n){
//     return fac[n]*_fac[k]%mod*_fac[n-k]%mod;
// }

// ll factorial(ll n, ll k){
//     ll ret = 1;
//     for(ll i = n; i >= n-k+1; i--){
//         ret = ret*i%mod;
//     }
//     return ret;
// }

const int maxN = 1e6+7;
int a[maxN];
int n;

class RollingHash{
public:

    static ll po(ll b, ll p, ll mod){
        b %= mod;
        p %= mod-1;
        ll r = 1;
        while(p){
            if(p&1)r = r*b%mod;
            p >>= 1;
            b = b*b%mod;
        }
        return r;
    }

    int n;
    int mod;
    int prm;
    vector<int> w;
    vector<int> _w;
    vector<int> pef;
    vector<int> suf;

    RollingHash(){}

    RollingHash(int _prm, int _mod, const string& s){
        prm = _prm;
        mod = _mod;
        build(s);
    }

    void build(const string& s){
        // initialize
        n = s.size();
        w.resize(n+2);
        _w.resize(n+2);
        pef.resize(n+2);
        suf.resize(n+2);

        // build w & _w
        w[0] = 1;
        for(int i = 1; i < w.size(); i++)w[i] = w[i-1]*1ll*prm%mod;
        _w.back() = po(w.back(), mod-2, mod);
        for(int i = w.size()-2; i >= 0; i--)_w[i] = _w[i+1]*1ll*prm%mod;

        // build pef & suf
        pef[0] = 0;
        for(int i = 0; i < n; i++){
            pef[i+1] = (pef[i] + w[i]*1ll*(s[i]-'a'+1))%mod;
        }
        suf[n] = 0;
        for(int i = n-1; i >= 0; i--){
            suf[i] = (suf[i+1] + w[n-i-1]*1ll*(s[i]-'a'+1))%mod;
        }
    }

    inline int getHash(int l, int r){
        return (pef[r+1] + 0ll + mod - pef[l]) %mod * _w[l] %mod;
    }

    inline int getRevHash(int l, int r){
        return (suf[l] + 0ll + mod - suf[r+1]) %mod * _w[n-r-1] %mod;
    }

    inline bool isEqual(int l1, int r1, int l2, int r2){
        return getHash(l1, r1) == getHash(l2, r2);
    }

    inline bool isRevEqual(int l1, int r1, int l2, int r2){
        return getRevHash(l1, r1) == getRevHash(l2, r2);
    }

    inline bool isPal(int l, int r){
        return getHash(l, r) == getRevHash(l, r);
    }
};

class MultiRollingHash{
public:

    static const int hashSize = 2;

    int mod[hashSize] = {(int)1e9+7, (int)1e9+9};
    int prm[hashSize] = {7, 13};
    RollingHash hashers[hashSize];

    MultiRollingHash(){}

    MultiRollingHash(const string& s){
        build(s);
    }

    void build(const string& s){
        int n = s.size();
        for(int ind = 0; ind < hashSize; ind++){
            hashers[ind] = RollingHash(prm[ind], mod[ind], s);
        }
    }
    
    vector<int> getHash(int l, int r){
        vector<int> ret;
        for(int ind = 0; ind < hashSize; ind++){
            ret.push_back(hashers[ind].getHash(l, r));
        }
        return ret;
    }

    vector<int> getRevHash(int l, int r){
        vector<int> ret;
        for(int ind = 0; ind < hashSize; ind++){
            ret.push_back(hashers[ind].getRevHash(l, r));
        }
        return ret;
    }

    bool isEqual(int l1, int r1, int l2, int r2){
        bool ret = 1;
        for(int ind = 0; ind < hashSize; ind++){
            ret &= hashers[ind].isEqual(l1, r1, l2, r2);
        }
        return ret;
    }

    bool isRevEqual(int l1, int r1, int l2, int r2){
        bool ret = 1;
        for(int ind = 0; ind < hashSize; ind++){
            ret &= hashers[ind].isRevEqual(l1, r1, l2, r2);
        }
        return ret;
    }

    bool isPal(int l, int r){
        for(int ind = 0; ind < hashSize; ind++){
            if(!hashers[ind].isPal(l, r))return 0;
        }
        return 1;
    }
};


bool isok(const string& s){
    MultiRollingHash rh(s);
    for(int i = 0; i < n; i++){
        if(!rh.isPal(i-a[i], i+a[i]))return 0;
        if(i-a[i] > 0 && i+a[i] < n-1)if(s[i-a[i]-1] == s[i+a[i]+1])return 0;
    }
    return 1;
}

void slv(){
    cin >> n;
    scan(a, n);
    vector<string> ans;
    for(int xx = 0; xx < 4; xx++){
        string b;
        int x0 = xx>>1&1;
        int x1 = xx&1;
        b.push_back(x0+'0');
        b.push_back(x1+'0');
        for(int i = 2; i < n; i++){
            b.push_back((a[i-1] == 0)^b[i-2]);
        }
        if(isok(b))ans.push_back(b);
    }
    cout << sz(ans) << '\n';
    cif(i, sz(ans)){
        cout << ans[i] << '\n';
    }
}

void prep(){
    
    // fac[0] = 1;
    // for(int i = 1; i < maxFac; i++)fac[i] = fac[i-1]*i%mod;
    // _fac[maxFac-1] = po(fac[maxFac-1], mod-2);
    // for(int i = maxFac-2; i >= 0; i--)_fac[i] = _fac[i+1]*(i+1)%mod;

    // w[0] = 1;
    // for(int i = 1; i < maxN; i++)w[i] = w[i-1]*p%mod;
    // _w[maxN-1] = po(w[maxN-1], mod-2);
    // for(int i = maxN-2; i >= 0; i--)_w[i] = _w[i+1]*p%mod;
    
}

signed main(){
    // if(fileName.size() > 0){
        // freopen("inp.txt", "r", stdin);
        // freopen("out.txt", "w", stdout);
    // }

    fastIO;

    // cout << fixed << setprecision (15);

    prep();
    
    int t = 1;
    cin >> t;
    while(t--){
        // cout << slv() << '\n';
        slv();
        // string s;
        // cin >> s;
        // bool x = slv();
        // cout << (x?"YES":"NO") << '\n';
    }
}       
/*

*/

In file included from /usr/include/c++/13/string:43,
                 from /usr/include/c++/13/bitset:52,
                 from /usr/include/x86_64-linux-gnu/c++/13/bits/stdc++.h:52,
                 from answer.code:16:
/usr/include/c++/13/bits/allocator.h: In destructor ‘std::__cxx11::basic_string<char>::_Alloc_hider::~_Alloc_hider()’:
/usr/include/c++/13/bits/allocator.h:184:7: error: inlining failed in call to ‘always_inline’ ‘std::allocator< <template-parameter-1-1> >::~allocator() noexcept [with _Tp = char]’: target specific option mismatch
  184 |       ~allocator() _GLIBCXX_NOTHROW { }
      |       ^
In file included from /usr/include/c++/13/string:54:
/usr/include/c++/13/bits/basic_string.h:181:14: note: called from here
  181 |       struct _Alloc_hider : allocator_type // TODO check __is_final
      |              ^~~~~~~~~~~~