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#include <iostream>
#include <fstream>
#include <stack>
#include <vector>
#include <deque>
#include <ctime>
#include <queue>
#include <cmath>
#define ll long long
#define ull unsigned long long
#define pb push_back
#define mp make_pair
using zint = int;
using namespace std;
const int inf = 3e4 + 5;
const int NMax = 1e5 + 5;
const int MMax = 2e5 + 5;
ifstream in("2sat.in");
ofstream out("2sat.out");
zint N,M,nrComp;
zint compOf[2*NMax],ans[NMax];
bool visStack[2*NMax],inComp[2*NMax],visComp[2*NMax];
pair<zint,zint> ex[MMax];
vector<zint> vEdge[2*NMax],vRev[2*NMax],comp[2*NMax];
stack<zint> st;
void getStack(zint);
void getComp(zint);
void getEdges(zint);
void update(zint,const zint);
bool eval(zint nr) {
zint x = ex[nr].first,
y = ex[nr].second,
val1 = ans[abs(x)],
val2 = ans[abs(y)];
if (x < 0) { val1 ^= 1; }
if (y < 0) { val2 ^= 1; }
return (val1 | val2);
}
#define inv(x) ((x > N) ? x-N : x+N)
int main() {
in>>N>>M;
for (int i=1;i <= M;++i) {
zint x,y;
in>>x>>y;
ex[i] = mp(x,y);
x = (x < 0) ? -x + N : x;
y = (y < 0) ? -y + N : y;
vEdge[inv(x)].pb(y);
vRev[y].pb(inv(x));
vEdge[inv(y)].pb(x);
vRev[x].pb(inv(y));
}
for (zint i = 1;i <= 2*N;++i) {
if (visStack[i]) {
continue;
}
getStack(i);
}
while (st.size()) {
zint node = st.top(); st.pop();
if (!inComp[node]) {
++nrComp;
getComp(node);
}
}
bool sol = true;
for (zint i=1;i <= N;++i) {
if (compOf[i] == compOf[i+N]) {
sol = false;
break;
}
}
if (sol) {
for (zint c=1;c <= nrComp;++c) {
update(c,0);
}
for (zint i=1;i <= N;++i) {
out<<ans[i]<<' ';
}
/*
//ans[1] ^= 1;
for (zint i=1;i <= M;++i) {
if (!eval(i)) {
cout<<"BAD\n";
break;
}
}
//*/
}
else {
out<<"-1\n";
}
in.close();out.close();
return 0;
}
void getStack(zint node) {
visStack[node] = true;
for (zint nxt : vEdge[node]) {
if (visStack[nxt]) {
continue;
}
getStack(nxt);
}
st.push(node);
}
void getComp(zint node) {
comp[nrComp].pb(node);
compOf[node] = nrComp;
inComp[node] = true;
for (zint nxt : vRev[node]) {
if (inComp[nxt]) {
continue;
}
getComp(nxt);
}
}
void update(zint c,const zint val) {
if (visComp[c]) {
return;
}
zint x = comp[c][0],
invx = (x > N) ? x-N : x+N,
comp2 = compOf[invx];
visComp[c] = true;
visComp[comp2] = true;
for (auto node : comp[c]) {
zint temp = val;
if (node > N) {
node -= N;
temp ^= 1;
}
ans[node] = temp;
}
}