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

void solve() {
    int n, k;
    cin >> n >> k;
    if (k == 0) {
        cout << string(n, '0') << "\n";
        return;
    }
    if (k == n) {
        cout << string(n, '1') << "\n";
        return;
    }
    
    int zeros = n - k;
    int left_zeros = zeros / 2;
    int right_zeros = zeros - left_zeros;
    
    string s = "";
    s.append(left_zeros, '0');
    s.append(k, '1');
    s.append(right_zeros, '0');
    
    if ((int)s.length() < n) {
        s.append(n - s.length(), '0');
    } else if ((int)s.length() > n) {
        s = s.substr(0, n);
    }
    
    cout << s << "\n";
}

int main() {
    ios_base::sync_with_stdio(0);
    cin.tie(0);
    
    int t;
    if (cin >> t) {
        while (t--) {
            solve();
        }
    }
    return 0;
}