#include <iostream>

#include <algorithm>

#include <vector>

#include <stack>

#include <set>

#include <queue>

#include <map>

typedeflonglongll;

using****namespacestd;

voidsolve14(){

** **map<ll,vector<ll>> s;

** **ll n,m;

** **s[0].push_back(0);

** **cin>>n>>m;

** **for (ll i=0; i<m; i++) {

** **ll j,l;

** **cin>>j>>l;

** **s[j].push_back(l);

** **}

** **for (ll i=1; i<=n; i++) {

** **cout<<s[i].size()<<" ";

** **sort(s[i].begin(),s[i].end());

** **for (ll j=0;j<s[i].size() ; j++) {

** **cout<<s[i][j]<<" ";

** **}

** **cout<<endl;

** **}

---

}

int main(){

** **int t=1;

** **//cin>>t;

** **while(t>0){

** **solve14();

** **t--;

** **}

** **return 0;

}

//用了map