#include <bits/stdc++.h>
#define endl "\n"
#define IOS                  \
    ios::sync_with_stdio(0); \
    cin.tie(0), cout.tie(0);
using namespace std;

typedef long long ll;
typedef pair<int, int> PII;
typedef pair<ll, ll> PLL;
typedef priority_queue<PII, vector<PII>, greater<PII>> Qu;
inline int read() { char c = getchar(); int tot = 1; while ((c < '0' || c>'9') && c != '-') c = getchar(); if (c == '-') { tot = -1; c = getchar(); }int sum = 0; while (c >= '0' && c <= '9') { sum = sum * 10 + c - '0'; c = getchar(); }return sum * tot; }
inline void write(ll x) { if (x < 0) putchar('-'), x = -x; if (x > 9) write(x / 10); putchar(x % 10 + '0'); }
const int N = 1e2 + 9;
const int INF = 0x3f3f3f3f;
const int M = 1e9 + 9;
const int Mod = 998244253;
vector<int>don[N], node[N];
int in[N], In[N];
int Sub[N];
int Pre[N];
void solve()
{
    int n ,m ;cin >> n >> m;
    for(int i = 1;i <= n;i++) {
        in[i] = In[i] = 0, Sub[i] = Pre[i] = 0;
        node[i].clear();
        don[i].clear();
    }
    for(int i = 1;i <= m;i++){
        int u ,v; cin >> u >> v;
        node[v].push_back(u);
        in[u] ++;
        In[v] ++;
        don[u].push_back(v);
    }

    int mid = (n + 1) / 2;
    queue<int> q;
    for(int i = 1;i <= n;i++){
        Pre[i] = 1;
        if(in[i] == 0) q.push(i); 
    }

    while(q.size()){
        int u = q.front() ; q.pop();
        for(int i = 0; i < node[u].size() ;i++){
            int v = node[u][i];
            Pre[v] += Pre[u]; // 当前点有几个肯定比他小的
            if( -- in[v] == 0){
                q.push(v);
            }
        }
    }
    for(int i = 1;i <= n;i++){
        if(in[i]){
            for(int i = 1;i <= n;i++) cout << 0 ;
            cout << endl;
            return ;
        }
        if(In[i] == 0) q.push(i);
        Sub[i] = 1;
    }
    while(q.size()){
        int u = q.front() ; q.pop();
        for(int i = 0; i < don[u].size() ;i++){
            int v = don[u][i];
            Sub[v] += Sub[u]; //     当前点有几个明确比他大的；
            if( -- In[v] == 0){
                q.push(v);
            }
        }
    }

    for(int i = 1;i <= n;i++){
        // cout << Pre[i] << " " << Sub[i] << endl;
        if(mid >= Pre[i] && mid <= n - Sub[i] + 1) cout << 1 ;
        else cout << 0 ;
    }
    cout << endl;
    return ;
}
int main()
{
    IOS;
    int ___ = 1; cin >> ___;
    for (int i = 1; i <= ___; i++)
        solve();
    return 0;
}