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#include <iostream>
#include <fstream>
#include <stack>
#include <vector>
#include <deque>
#include <ctime>
#include <queue>
#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,P;
zint sol[NMax],aux[NMax];
pair<zint,zint> ex[MMax];
struct elem {
zint lit,nrE;
elem (zint _lit = 0,zint _nrE = 0) {
lit = _lit;
nrE = _nrE;
}
};
vector<elem> v[NMax];
bool test(zint,zint);
bool eval(zint);
void cpy(zint*,zint*);
int main() {
in>>N>>M;
for (int i=1;i <= M;++i) {
zint x,y;
in>>x>>y;
ex[i] = mp(x,y);
v[abs(x)].pb( elem(abs(y),i) );
v[abs(y)].pb( elem(abs(x),i) );
}
for (int i=1;i <= N;++i) {
sol[i] = -1;
}
bool ans = true;
for (int i=1;i <= N;++i) {
if (sol[i] != -1) {
continue;
}
cpy(aux,sol);
bool ok = false;
if (test(i,0)) {
//sol[i] = 0;
ok = true;
}
else if (test(i,1)) {
//sol[i] = 1;
ok = true;
}
if (ok) {
cpy(sol,aux);
}
else {
ans = false;
break;
}
}
if (ans) {
for (int i=1;i <= N;++i) {
out<<sol[i]<<' ';
}
for (int i=1;i <= M;++i) {
if (!eval(i)) {
cout<<"BAD\n";
break;
}
}
}
else {
out<<"-1\n";
}
in.close();out.close();
return 0;
}
bool test(zint idx,zint val) {
bool vis[NMax] = {};
aux[idx] = val;
queue<zint> Q;
Q.push(idx);
while (Q.size()) {
zint lit = Q.front();
Q.pop();
for (elem el : v[lit]) {
zint nxt = el.lit, nr = el.nrE;
if (vis[nxt]) {
if ( !eval(nr) ) {
return false;
}
continue;
}
bool val0 = false, val1 = false;
aux[nxt] = 0;
if ( eval(nr) ) {
val0 = true;
}
aux[nxt] = 1;
if ( eval(nr) ) {
val1 = true;
}
if (val0) {
if (val1) {
continue;
}
aux[nxt] = 0;
}
else if (val1) {
aux[nxt] = 1;
}
vis[nxt] = true;
Q.push(nxt);
}
}
return true;
}
bool eval(zint nr) {
zint x = ex[nr].first,
y = ex[nr].second,
val1 = aux[abs(x)],
val2 = aux[abs(y)];
if (x < 0) { val1 ^= 1; }
if (y < 0) { val2 ^= 1; }
return (val1 | val2);
}
void cpy(zint* a,zint* b) {
for (int i=1;i <= N;++i) {
a[i] = b[i];
}
}