//Be Name KHODA
#pragma GCC optimize("O3")
#include<bits/stdc++.h>
using namespace std;
typedef long long ll;
typedef long double ld;
#define pb push_back
#define pp pop_back
#define lb lower_bound
#define ub upper_bound
#define cl clear
#define bg begin
#define arr(x) array<int , x>
#define endl '\n'
int n , m;
vector<array<ll , 2>> bls;
arr(2) lst[4];
int infs[100000][3];
int mns[2000000][2];
vector<int> o;
void addLst(int li , int i){
if(lst[li][1] == 0) infs[i][0] = -1;
else infs[i][0] = lst[li][0] , infs[lst[li][0]][1] = i;
lst[li][0] = i , lst[li][1]++ , infs[i][1] = -1;
}
void delLst(int li , int i){
if(infs[i][1] == -1) lst[li][0] = infs[i][0];
else infs[infs[i][1]][0] = infs[i][0];
if(infs[i][0] != -1) infs[infs[i][0]][1] = infs[i][1];
lst[li][1]--;
}
void add(int c , ll x){
int len = (int)bls.size();
if(!bls.empty() and bls[len - 1][0] == c) bls[len - 1][1] += x;
else bls.pb({c , x});
}
int clc(int i , bool sgn){
ll ln = n;
if(sgn) return (3 * ((bls[i][1] + ln - 1) / ln));
int res = 3 * (bls[i][1] / (ln + 2));
if(bls[i][1] % (ln + 2) > 2) res += 3;
else res += bls[i][1] % (ln + 2);
return res;
}
void clcO(int i , int sgn){
ll ln = n;
if(sgn == bls[i][0]){
ll d = bls[i][1];
while(d > 0) o.pb(min(ln , d) - 1) , o.pb(sgn) , o.pb(sgn) , d -= min(ln , d);
}else{
ll d = bls[i][1];
while(d > 3) o.pb(min(ln + 2 , d) - 3) , o.pb(bls[i][0]) , o.pb(sgn) , d -= min(ln + 2 , d);
for(int j = 0 ; j < d ; j++) o.pb(bls[i][0]);
}
}
void f(){
int mn = 0;
lst[0] = {-1 , 0};
lst[1] = lst[0] , lst[2] = lst[0] , lst[3] = lst[0];
addLst(0 , 0);
for(int i = 1 ; i < n ; i++) addLst(3 , i) , infs[i][2] = 3;
int len = (int)bls.size();
for(int i = 0 ; i < len ; i++){
int d = clc(i , 1) - clc(i , 0);
int inx = bls[i][0];
if(d > 0){
delLst(infs[inx][2] - mn , inx);
int dd = infs[inx][2] - mn + d;
if(dd <= 3) addLst(dd , inx);
while(lst[0][1] == 0) mn++ , lst[0] = lst[1] , lst[1] = lst[2] , lst[2] = lst[3] , lst[3] = {-1 , 0};
infs[inx][2] = min(d + infs[inx][2] , mn + 3);
if(dd > 3) addLst(infs[inx][2] - mn , inx);
}
mns[i][0] = lst[0][0] , mns[i][1] = mn;
}
int e = mns[len - 1][0] , sz = mns[len - 1][1];
for(int i = len - 1 ; i >= 0 ; i--){
clcO(i , e);
if(i == 0){
if(e != 0) o.pb(0) , o.pb(e) , o.pb(0);
}else{
int d = 0;
if(bls[i][0] == e) d = clc(i , 1) - clc(i , 0);
if(mns[i - 1][1] + 3 + d == sz) o.pb(0) , o.pb(e) , o.pb(mns[i - 1][0]) , e = mns[i - 1][0] , sz = mns[i - 1][1];
else sz -= d;
}
}
}
int main(){
ios::sync_with_stdio(0);
cin.tie(0);
int e = 0;
cin >> n >> m;
for(int i = 0 ; i < m ;){
int d;
cin >> d;
if(d != e) add(d , 1) , i++;
else{
int d1 , d2;
cin >> d1 >> d2;
if(d1 != e and d2 == 0) e = d1;
else if(d1 == e) add(e , d2 + 1);
else add(d1 , d2 + 3);
i += 3;
}
}
f();
cout << (int)o.size() << endl;
for(int i = (int)o.size() - 1 ; i >= 0 ; i--) cout << o[i] << " ";
}
