#include <bits/stdc++.h>
using namespace std;
 
#define ms(s, n) memset(s, n, sizeof(s))
#define FOR(i, a, b) for (int i = (a); i < (b); i++)
#define FORd(i, a, b) for (int i = (a) - 1; i >= (b); i--)
#define FORall(it, a) for (__typeof((a).begin()) it = (a).begin(); it != (a).end(); it++)
#define sz(a) int((a).size())
#define present(t, x) (t.find(x) != t.end())
#define all(a) (a).begin(), (a).end()
#define uni(a) (a).erase(unique(all(a)), (a).end())
#define pb push_back
#define pf push_front
#define mp make_pair
#define fi first
#define se second
#define prec(n) fixed<<setprecision(n)
#define bit(n, i) (((n) >> (i)) & 1)
#define bitcount(n) __builtin_popcountll(n)
typedef long long ll;
typedef unsigned long long ull;
typedef long double ld;
typedef pair<int, int> pi;
typedef vector<int> vi;
typedef vector<pi> vii;
const int MOD = (int) 1e9 + 7;
const int MOD2 = 1007681537;
const int INF = (int) 1e9;
const ll LINF = (ll) 1e18;
const ld PI = acos((ld) -1);
const ld EPS = 1e-12;
inline ll gcd(ll a, ll b) {ll r; while (b) {r = a % b; a = b; b = r;} return a;}
inline ll lcm(ll a, ll b) {return a / gcd(a, b) * b;}
inline ll fpow(ll n, ll k, int p = MOD) {ll r = 1; for (; k; k >>= 1) {if (k & 1) r = r * n % p; n = n * n % p;} return r;}
template<class T> inline int chkmin(T& a, const T& val) {return val < a ? a = val, 1 : 0;}
template<class T> inline int chkmax(T& a, const T& val) {return a < val ? a = val, 1 : 0;}
inline ll isqrt(ll k) {ll r = sqrt(k) + 1; while (r * r > k) r--; return r;}
inline ll icbrt(ll k) {ll r = cbrt(k) + 1; while (r * r * r > k) r--; return r;}
inline void addmod(int& a, int val, int p = MOD) {if ((a = (a + val)) >= p) a -= p;}
inline void submod(int& a, int val, int p = MOD) {if ((a = (a - val)) < 0) a += p;}
inline int mult(int a, int b, int p = MOD) {return (ll) a * b % p;}
inline int inv(int a, int p = MOD) {return fpow(a, p - 2, p);}
inline int sign(ld x) {return x < -EPS ? -1 : x > +EPS;}
inline int sign(ld x, ld y) {return sign(x - y);}
#define db(x) cerr << #x << " = " << (x) << " ";
#define endln cerr << "\n";
 
const int maxn = 1000 + 5;
 
int ff(int x) {return x * x;}
 
void solve(int n, long long k) {
    static int g[maxn][maxn];
    static int pts[maxn];
    FOR(i, 0, n) fill_n(g[i], n, 0);
    fill_n(pts, n, 0);
    for (int i = 1; i < n; i += 2) {
        int u = i >> 1;
        FOR(j, 0, u) {
            g[i][j] = 1;
            pts[i]++;
            if (i + 1 < n) {
                g[j][i + 1] = 1;
                pts[j]++;
            }
        }
        FOR(j, u, i) {
            g[j][i] = 1;
            pts[j]++;
            if (i + 1 < n) {
                g[i + 1][j] = 1;
                pts[i + 1]++;
            }
        }
        if (i + 1 < n) {
            g[i][i + 1] = 1;
            pts[i]++;
        }
    }
    long long score = 0;
    FOR(i, 0, n) score += ff(pts[i]);
    static int used[maxn];
    fill_n(used, n, 0);
    while (score < k) {
        pi best;
        FOR(i, 0, n) if (!used[i]) chkmax(best, mp(pts[i], i));
        int u = best.se;
        used[u] = 1;
        int found = 0;
        FOR(i, 0, n) if (!used[i] && g[i][u]) {
            int dif = ff(pts[u] + 1) - ff(pts[u]) - ff(pts[i]) + ff(pts[i] - 1);
            if (score + dif <= k) {
                score += dif;
                g[i][u] ^= 1, g[u][i] ^= 1;
                pts[u]++, pts[i]--;
            }
        }
    }
    fill_n(pts, n, 0);
    FOR(i, 0, n) FOR(j, i + 1, n) {
        assert(g[i][j] + g[j][i] == 1);
        if (g[i][j]) {
            pts[i]++;
        }
        else {
            pts[j]++;
        }
    }
    score = 0;
    FOR(i, 0, n) score += ff(pts[i]);
    assert(score == k);
    FOR(i, 0, n) {
        FOR(j, 0, n) cout << g[i][j];
        cout << "\n";
    }
}
 
long long fmin(int n) {
    if (n & 1) {
        int d = (n - 1) / 2;
        return (long long) n * d * d;
    }
    else {
        int d = (n - 2) / 2;
        return ((long long) d * d + (long long) (d + 1) * (d + 1)) * n / 2;
    }
}
 
long long fmax(int n) {
    return (long long) (n - 1) * n * (2 * n - 1) / 6;
}
 
void solve() {
    int test; cin >> test;
    assert(1 <= test && test <= 100);
    int ntot = 0;
    while (test--) {
        int n, k; cin >> n >> k;
        assert(1 <= n && n <= 1000 && 1 <= k && k <= 1e9);
        ntot += n;
        if (!(fmin(n) <= k && k <= fmax(n) && (k + fmin(n) + 1 & 1))) {
            cout << -1 << "\n";
            continue;
        }
        solve(n, k);
    }
    assert(ntot <= 1e4);
}
 
int main() {
    int JUDGE_ONLINE = 1;
    if (fopen("in.txt", "r")) {
        JUDGE_ONLINE = 0;
        assert(freopen("in.txt", "r", stdin));
        assert(freopen("out.txt", "w", stdout));
    }
    else {
        ios_base::sync_with_stdio(0), cin.tie(0);
    }
    solve();
    if (!JUDGE_ONLINE) {
        //cout << "\nTime elapsed: " << 1000 * clock() / CLOCKS_PER_SEC << "ms\n";
    }
    return 0;
}