#include <bits/stdc++.h>
using namespace std;
#define MOD 998244353
#define INF 1000000001
#define LNF 1000000000000000001
#define int ll
typedef long long ll;
typedef pair<int,int> pii;
void solve(){
//#define TEST
int n,m;cin >> n >> m;
if(m > n){
cout << "0";
return;
}
vector<int> net(n);
for(int i = 0;i < n;i++){
cin >> net[i];
}
vector<int> ret(m);
vector<vector<pii>> edge(n);
for(int i = 0;i < m;i++){
int a,b;cin >> a >> b;
edge[a].emplace_back(b,i);
edge[b].emplace_back(a,i);
}
stack<int> leaf;
vector<int> sizes(n);
vector<int> removed(n);
for(int i = 0;i < n;i++){
sizes[i] = edge[i].size();
if(edge[i].size() == 1){
leaf.push(i);
}
}
while(!leaf.empty()){
int top = leaf.top();
leaf.pop();
removed[top] = true;
pii parent;
for(auto i : edge[top]){
if(!removed[i.first])
parent = i;
}
ret[parent.second] = -net[top]*2;
sizes[top]--;
sizes[parent.first]--;
if(sizes[parent.first] == 1){
leaf.push(parent.first);
}
}
int left = 0;
for(int i = 0;i < n;i++){
if(!removed[i])
left++;
}
if(left == 0){
for(int i : ret)
cout << i << ' ';
return;
} else if(left%2 == 0){
cout << '0';
return;
}
}
signed main(){
cin.tie(0);
ios_base::sync_with_stdio(0);
#ifdef DEBUG
freopen("i.txt","r",stdin);
freopen("o.txt","w",stdout);
#endif
int t = 1;
#ifdef TEST
cin >> t;
#endif
while(t--){
solve();
}
return 0;
}
