#include<cstdio>

 #include<algorithm>

 #include<cstring>

 #define rep(i,l,r) for (int i=(l); i<=(r); i++)

 using namespace std;

 const int N=;

 int T,n,m,top,cnt,u,v;

 int fa[N],sz[N],d[N],ans[N],h[N],nxt[N],to[N];

 struct P{ int a,b,c; }s[*N];

 struct S{ int x,y; };

 void add(int u,int v){ to[++cnt]=v; nxt[cnt]=h[u]; h[u]=cnt; }

 void init(){ cnt=; rep(i,,n) fa[i]=i,sz[i]=,d[i]=,h[i]=; }

 S get(int x){

     if (fa[x]==x) return (S){x,};

     S t=get(fa[x]); return (S){t.x,t.y^d[x]};

 }

 void uni(int x,int y){

     int t1=get(x).y; x=get(x).x;

     int t2=get(y).y; y=get(y).x;

     if (sz[x]<sz[y]) swap(x,y);

     s[++top]=(P){,y,y}; s[++top]=(P){,x,sz[x]}; s[++top]=(P){,y,};

     fa[y]=x; d[y]=t1^t2^; sz[x]+=sz[y];

 }

 void cancel(int x){

     if (s[x].a==) fa[s[x].b]=s[x].c;

     if (s[x].a==) sz[s[x].b]=s[x].c;

     if (s[x].a==) d[s[x].b]=s[x].c;

 }

 void solve(int l,int r){

     if (l==r) { ans[l]=; return; }

     int mid=(l+r)>>,tmp=top; bool flag=;

     rep(u,mid+,r)

         for (int i=h[u]; i; i=nxt[i]){

             int v=to[i];

             if (v>=l && v<=mid) continue;

             if (get(u).x!=get(v).x) uni(u,v);

             else if (get(u).y==get(v).y) { flag=; break; }

         }

     if (flag) rep(i,l,mid) ans[i]=; else solve(l,mid);

     while (top>tmp) cancel(top--); flag=;

     rep(u,l,mid)

         for (int i=h[u]; i; i=nxt[i]){

             int v=to[i];

             if (v>mid && v<=r) continue;

             if (get(u).x!=get(v).x) uni(u,v);

             else if (get(u).y==get(v).y) { flag=; break; }

         }

     if (flag) rep(i,mid+,r) ans[i]=; else solve(mid+,r);

     while (top>tmp) cancel(top--);

 }

 int main(){

     freopen("hdu5354.in","r",stdin);

     freopen("hdu5354.out","w",stdout);

     for (scanf("%d",&T); T--; ){

         scanf("%d%d",&n,&m); init();

         rep(i,,m) scanf("%d%d",&u,&v),add(u,v),add(v,u);

         solve(,n);

         rep(i,,n) printf("%d",ans[i]); puts("");

     }

     return ;

 }