#include<bits/stdc++.h>
#define int long long
using namespace std;
inline int read(){int x=0,f=1;char ch=getchar();while(ch<'0' || ch>'9'){if(ch=='-')f=-1;ch=getchar();}while(ch>='0' && ch<='9')x=(x<<3)+(x<<1)+(ch^'0'),ch=getchar();return x*f;}
inline void write(int x){if(x<0)putchar('-'),x=-x;if(x>=10)write(x/10);putchar((x%10)^'0');}
struct exprque{
    priority_queue<int,vector<int>,greater<int>>q,dq;
    void push(int x){
        q.push(x);
    }
    void erase(int x){
        dq.push(x);
    }
    void ex(){
        while(!q.empty() && !dq.empty() && q.top()==dq.top()){
            q.pop();
            dq.pop();
        }
    }
    bool empty(){
        ex();
        return q.empty();
    }
    int top(){
        return q.top();
    }
}qu;
int cnt,a[100005];
bool v[100005];
vector<int>l[100005];
void dfs(int i){
    a[++cnt]=i;
    priority_queue<int,vector<int>,greater<int>>q;
    for(int j=0;j<l[i].size();++j){
        int u=l[i][j];
        q.push(u);
    }
    while(!q.empty()){
        if(!v[q.top()]){
            int u=q.top();
            v[u]=1;
            qu.erase(u);
            while(!qu.empty() && qu.top()<q.top()){
                int nu=qu.top();
                v[nu]=1;
                qu.erase(nu);
                dfs(nu);
            }
            dfs(u);
        }
        q.pop();
    }
}
void main1(){
    memset(a,0,sizeof(a));
    memset(v,0,sizeof(v));
    int n=read(),m=read(),x,y;
    for(int i=1;i<=n;++i){
        qu.push(i);
    }
    for(int i=0;i<m;++i){
        x=read(),y=read();
        l[x].push_back(y);
        l[y].push_back(x);
    }
    cnt=0;
    while(!qu.empty()){
        int u=qu.top();
        v[u]=1;
        qu.erase(u);
        dfs(u);
    }
    for(int i=1;i<=n;++i){
        write(a[i]);
        putchar(' ');
    }
    return;
}
signed main(){
    freopen("graperm.in","r",stdin);
    freopen("graperm.out","w",stdout);
    int c=read(),t=read();
    while(t--){
        main1();
        putchar('\n');
    }
    return 0;
}