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#include <algorithm>
#include <cstdio>
using namespace std;
class P2SAT {
public:
P2SAT(const int N) {
Size = 2 * N + 2;
Offset = N;
G = vector< vector<int> >(Size);
Gt = G;
values = vector<int>(Size, 0);
used = vector<bool>(Size, false);
}
void addRel(int x, int y) {
addEdge(Offset - x, Offset + y);
addEdge(Offset - y, Offset + x);
}
void addMust(int x) {
addEdge(Size - 1, Offset + x);
addEdge(Offset - x, Offset);
}
vector<int> getValues() {
stk.reserve(Size);
for (int i = 0; i < Size; ++i)
if (!used[i])
Dfs1(i);
fill(used.begin(), used.end(), false);
Dfs2(Offset);
for (int i = Size - 1; i >= 0; --i)
if (!values[stk[i]] && !values[Non(stk[i])])
Dfs2(stk[i]);
stk.clear();
if (values[Offset] == -1) return vector<int>(1, -1);
for (int i = 0; i <= Offset; ++i)
if (values[i] == values[Non(i)]) return vector<int>(1, -1);
vector<int> ret(Offset + 1);
for (int i = 1; i <= Offset; ++i)
ret[i] = values[Offset + i];
return ret;
}
private:
vector< vector<int> > G, Gt;
vector<int> values, stk;
vector<bool> used;
int Offset, Size;
void addEdge(int x, int y) {
G[x].push_back(y);
Gt[y].push_back(x);
}
void Dfs1(const int node) {
used[node] = 1;
for (int p: G[node])
if (!used[p]) Dfs1(p);
stk.push_back(node);
}
void Dfs2(const int node) {
used[node] = 1;
if (values[node])
values[Offset] = -1;
values[Non(node)] = 1;
for (int p: Gt[node])
if (!used[p]) Dfs2(p);
}
int Non(const int n) const {
if (n == Offset) return Size - 1;
if (n == Size - 1) return Offset;
return 2 * Offset - n;
}
};
int main()
{
freopen("2sat.in", "r", stdin);
freopen("2sat.out", "w", stdout);
int N, M;
scanf("%d%d", &N, &M);
P2SAT S(N);
while (M--) {
int x, y;
scanf("%d%d", &x, &y);
S.addRel(x, y);
}
vector<int> sol = S.getValues();
if (sol == vector<int>(1, -1)) puts("-1\n");
else
for (int i = 1; i <= N; ++i)
printf("%d ", sol[i]);
}