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#include<stdio.h>
int n,m,i,j,r,k,p[200001],a[200001],b[200001],w[200001],c[200001],*f[200001],*g[200001],u[200001],v[200001];
void A(int x) {
c[x]=1;
for(int i=0;i<u[x];i++)
if(!c[f[x][i]])
A(f[x][i]);
w[++r]=x;
}
void B(int x) {
c[x]=0;
if(p[x]==2) {
p[x]=0;
if(x>n)
p[x-n]=1;
else
p[x+n]=1;
}
for(int i=0;i<v[x];i++)
if(c[g[x][i]])
B(g[x][i]);
}
int main() {
freopen("2sat.in","r",stdin),freopen("2sat.out","w",stdout),scanf("%d%d",&n,&m);
for(i=1;i<=m;i++) {
scanf("%d%d",&a[i],&b[i]);
if(a[i]<0)
a[i]=n-a[i];
if(b[i]<0)
b[i]=n-b[i];
if(a[i]>n)
u[a[i]-n]++,v[b[i]]++;
else
u[a[i]+n]++,v[b[i]]++;
if(b[i]>n)
u[b[i]-n]++,v[a[i]]++;
else
u[b[i]+n]++,v[a[i]]++;
}
for(i=1;i<=2*n;i++)
f[i]=new int[u[i]],g[i]=new int[v[i]],u[i]=v[i]=0,p[i]=2;
for(i=1;i<=m;i++) {
if(a[i]>n)
f[a[i]-n][u[a[i]-n]++]=b[i],g[b[i]][v[b[i]]++]=a[i]-n;
else
f[a[i]+n][u[a[i]+n]++]=b[i],g[b[i]][v[b[i]]++]=a[i]+n;
if(b[i]>n)
f[b[i]-n][u[b[i]-n]++]=a[i],g[a[i]][v[a[i]]++]=b[i]-n;
else
f[b[i]+n][u[b[i]+n]++]=a[i],g[a[i]][v[a[i]]++]=b[i]+n;
}
for(j=1;j<=2*n;j++)
if(!c[j])
A(j);
for(i=r;i;i--)
if(c[i])
B(w[i]);
for(j=1;j<=n;j++)
if(p[j]==2)
p[j]=0,p[j+n]=1;
for(i=1;i<=m;i++)
if(!p[a[i]]&&!p[b[i]]) {
p[a[i]]=1;
if(a[i]>n)
p[a[i]-n]=0;
else
p[a[i]+n]=0;
}
for(k=0,j=1;j<=m;j++)
if(!p[a[j]]&&!p[b[j]])
k=1;
if(!k)
for(i=1;i<=n;i++)
printf("%d ",p[i]);
else
printf("-1");
}