#include <bits/stdc++.h>
using namespace std;
#define int long long
#define double long double
#define FOR(i, l, r, d) for(int i=(l); i<=(r); i+=(d))
#define szof(x) ((int)(x).size())
#define vi vector<int>
#define pii pair<int,int>
#define F first
#define S second
#define pb push_back
#define eb emplace_back
#define mkp make_pair
const int INF = 2147483647;
const int LNF = INF*INF;
const int MOD = 1000000007;
const int mod = 998244353;
//#pragma GCC optimize("Ofast")
//#pragma GCC optimize("unroll-loops")
const int MAX = 100010;
int n, m;
int L[MAX], R[MAX];
int cnt1[MAX], cnt2[MAX];
int res[MAX];
bool solved;
void check(int mask){
vi arr;
FOR(i, 0, m-1, 1){
if((mask & (1<<i)) != 0){
arr.pb(1);
}
else{
arr.pb(0);
}
}
FOR(i, 1, n, 1){
cnt1[i] = 0;
cnt2[i] = 0;
}
FOR(i, 0, m-1, 1){
if(arr[i]==1){
if(L[i] <= R[i]){
FOR(j, L[i], R[i], 1){
cnt1[j]++;
}
}
else{
FOR(j, L[i], n, 1){
cnt1[j]++;
}
FOR(j, 1, R[i], 1){
cnt1[j]++;
}
}
}
else{
if(L[i] <= R[i]){
FOR(j, L[i], R[i], 1){
cnt2[j]++;
}
}
else{
FOR(j, L[i], n, 1){
cnt2[j]++;
}
FOR(j, 1, R[i], 1){
cnt2[j]++;
}
}
}
}
bool flag = 1;
FOR(i, 1, n, 1){
if(cnt1[i]==0 or cnt2[i]==0){
flag = 0;
}
}
if(flag){
solved = 1;
FOR(i, 0, m-1, 1){
res[i] = arr[i];
}
}
}
signed main(){
ios_base::sync_with_stdio(false);
cin.tie(0);
cout.tie(0);
cin>>n>>m;
FOR(i, 0, m-1, 1){
cin>>L[i]>>R[i];
}
solved = 0;
FOR(mask, 0, (1<<m)-1, 1){
check(mask);
}
if(solved){
FOR(i, 0, m-1, 1){
cout<<res[i];
}
cout<<'\n';
}
else{
cout<<"impossible"<<'\n';
}
return 0;
}
