#include<cstdio>

#include<cstdlib>

#define N 3010

int n,m,i,j,k,a[N],del[N],fin[N];bool g[N][N];

inline void swap(int&a,int&b){int c=a;a=b;b=c;}

inline void read(int&a){char c;while(!(((c=getchar())>='0')&&(c<='9')));a=c-'0';while(((c=getchar())>='0')&&(c<='9'))(a*=10)+=c-'0';}

int main(){

  read(n),read(m);

  while(m--)read(i),read(j),g[i-1][j-1]=g[j-1][i-1]=1;

  for(i=0;i<n;i++)a[i]=i;

  while(1){

    for(i=0;i<n;i++)swap(a[i],a[std::rand()%n]);

    for(i=0;i<n;i++)del[i]=0;

    for(k=i=0;i<n;i++)if(!del[i])for(k++,j=i+1;j<n;j++)if(!g[a[i]][a[j]])del[j]=1;

    if(k>=n/3){

      for(i=j=0;i<n;i++)if(!del[i])fin[j++]=a[i];

      for(i=0;i<n/3;i++)printf("%d ",fin[i]+1);

      return 0;

    }

  }

}