// compile: make data
// run: ./data < data.in
#include <bits/stdc++.h>
using namespace std;
#pragma GCC optimize("O3,unroll-loops")
#pragma GCC target("avx2,bmi,bmi2,lzcnt,popcnt")
#ifdef LOCAL
#include <debug/codeforces.h>
#define debug(x...) _debug_print(#x, x);
#define Debug(x...) _debug_print_format(#x, x);
#else
#define debug(x...)
#define Debug(x...)
#endif
template<typename...Args> void print_(Args...args){((cout<<args<<" "),...)<<endl;}
#define VI vector<int>
#define VII vector<vector<int>>
#define VIII vector<vector<vector<int>>>
#define rep(i,a,b) for(int i=(a);i<(int)(b);++i)
#define sz(v) ((int)(v).size())
#define print(...) print_(__VA_ARGS__);
#define FIND(a, x) ((find(a.begin(),a.end(),(x))!=a.end())?1:0)
#define cmin(x,...) x=min({(x), __VA_ARGS__})
#define cmax(x,...) x=max({(x), __VA_ARGS__})
#define INTMAX (int)(9223372036854775807)
#define INF (int)(1152921504606846976)
#define double long double
#define int long long
#define MAXN 200010
struct graph {
struct node {
int v, w;
bool operator<(const node &other) const {
return w < other.w;
}
bool operator==(const node &other) const {
return v == other.v && w == other.w;
}
};
vector<vector<node>> e;
int n;
bool directed;
graph(int V, bool D = 0) {
n = V;
e.resize(n);
directed = D;
}
void add_edge(int u, int v, int w = 1) {
e[u].push_back(node{v, w});
}
void tarjan_scc(vector<vector<int>> &scc, vector<int> &belong) {
stack<int> s;
vector<int> dfn(n), low(n), instack(n);
int dfncnt;
scc.clear(), belong.resize(n, -1);
function<void(int)> dfs = [&](int u) {
low[u] = dfn[u] = ++dfncnt, s.push(u), instack[u] = 1;
for (auto edge: e[u]) {
int v = edge.v;
if (!dfn[v]) dfs(v), cmin(low[u], low[v]);
else if (instack[v]) cmin(low[u], dfn[v]);
}
if (dfn[u] == low[u]) {
scc.push_back(vector<int>{});
while (s.top() != u) {
belong[s.top()] = sz(scc) - 1;
scc.back().push_back(s.top());
instack[s.top()] = 0, s.pop();
}
belong[s.top()] = sz(scc) - 1;
scc.back().push_back(s.top());
instack[s.top()] = 0, s.pop();
}
};
rep(i, 0, n) if (!~belong[i]) dfs(i);
}
int topo(vector<int> &vs) {
vector<int> din(n, 0);
for (auto es: e) for (auto edge: es) ++din[edge.v];
queue<int> q;
rep(i, 0, n) if (!din[i]) q.push(i);
vs.clear();
while (!q.empty()) {
int u = q.front(); q.pop();
vs.push_back(u);
for (auto [v, _]: e[u]) {
if (!--din[v]) q.push(v);
}
}
return sz(vs) == n;
}
graph contract(vector<vector<int>> &scc, vector<int> &belong) {
tarjan_scc(scc, belong);
int V = sz(scc);
graph dag(V, 1);
vector<int> vis(V, 0);
for (auto comp: scc) {
for (auto u: comp) {
for (auto edge: e[u]) {
int v = edge.v;
if (belong[u] != belong[v]) {
dag.add_edge(belong[u], belong[v]);
vis[belong[v]] = 1;
}
}
}
for (auto u: comp) for (auto edge: e[u]) if (belong[u] != belong[edge.v]) vis[belong[edge.v]] = 0;
}
return dag;
}
int twosat(vector<int> &ans) {
vector<vector<int>> scc; vector<int> belong; auto dag = contract(scc, belong);
int V = n >> 1;
rep(i, 0, V) if (belong[i] == belong[i + V]) return 0;
vector<int> vs; dag.topo(vs);
vector<int> idx(dag.n);
rep(i, 0, dag.n) idx[vs[i]] = i;
ans.assign(V, 0);
rep(i, 0, V) if (idx[belong[i]] > idx[belong[i + V]]) ans[i] = 1;
return 1;
}
void graphviz_dump(string filename = "graph.dot") {
ofstream gf; gf.open(filename);
gf << (directed ? "digraph" : "graph") << " {\n";
gf << " "; rep(i, 0, n) gf << i << " ;"[i==n-1]; gf << endl;
string notation = directed ? " -> " : " -- ";
bool weighted = 0;
for (auto es: e) for (auto edge: es) if (edge.w != 1) weighted = 1;
rep(u, 0, n) {
for (auto [v, w]: e[u]) {
if (!directed && u > v) continue;
gf << " " << u << notation << v << (weighted ? " ;\n" : ";\n");
}
}
gf << "}\n";
}
};
int32_t main() {
ios::sync_with_stdio(false); cin.tie(nullptr); cout.tie(nullptr);
int n, m; cin >> n >> m;
graph g(2*m, 1);
rep(i, 0, n) {
string su, sv; int u, v; cin >> su >> u >> sv >> v; --u, --v;
if (su[0] == '+' && sv[0] == '+') g.add_edge(m+u, v), g.add_edge(m+v, u);
else if (su[0] == '-' && sv[0] == '-') g.add_edge(u, m+v), g.add_edge(v, m+u);
else if (su[0] == '+' && sv[0] == '-') g.add_edge(m+u, m+v), g.add_edge(v, u);
else if (su[0] == '-' && sv[0] == '+') g.add_edge(u, v), g.add_edge(m+v, m+u);
}
// g.graphviz_dump();
vector<int> ans;
int valid = g.twosat(ans);
if (!valid) cout << "IMPOSSIBLE" << endl;
else {
rep(i, 0, m) cout << (ans[i] ? '+' : '-') << " ";
cout << endl;
}
return 0;
}
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