#include <bits/stdc++.h>
using namespace std;
#define ll long long
#define MAXN 100005
#define MAXM 500005
#define FOR(i, a, b) for(ll i = a; i <= b; i++)
#define f first
#define s second
ll n, m, t[MAXN], en[MAXN], r[MAXM];
pair<ll, ll> e[MAXM];
vector<pair<ll, ll>> adj[MAXN];
bool v[MAXN];
int main(){
cin >> n >> m;
FOR(i, 1, n) {
cin >> t[i];
en[i] = 0, v[i] = false;
}
FOR(i, 1, m){
cin >> e[i].f >> e[i].s;
adj[e[i].f].push_back({e[i].s, i}), en[e[i].f]++;
adj[e[i].s].push_back({e[i].f, i}), en[e[i].s]++;
r[i] = 1000000001;
}
if(!(m == n - 1 || m == n)) return cout << 0 << endl, 0;
queue<ll> q;
FOR(i, 1, n) if(en[i] == 1) q.push(i);
ll d = n;
while(q.size()){
ll qi = q.front(); q.pop();
if(v[qi]) continue;
v[qi] = true, d--;
if(en[qi] == 0) continue;
for(pair<ll, ll> p : adj[qi]) if(r[p.s] == 1000000001) {
r[p.s] = 2 * t[qi];
t[p.f] -= t[qi], en[p.f]--;
if(!v[p.f] && en[p.f] == 1) q.push(p.f);
}
}
if(d != 0 && d % 2 == 0) return cout << 0 << endl, 0;
ll prvi = -1, stt, ci = -1, fe = 0;
FOR(i, 1, n) if(!v[i]) ci = i;
if(ci == -1) {
FOR(i, 1, m) cout << r[i] << endl;
return 0;
}
stt = ci;
stack<ll> st;
ll alts = 0;
do{
for(pair<ll, ll> p : adj[ci]) if(r[p.s] == 1000000001 && !(e[p.s].f == prvi || e[p.s].s == prvi)) {
prvi = ci, ci = p.f;
if(stt != ci) alts = t[p.f] - alts;
if(fe == 0) fe = p.s;
break;
}
st.push(ci);
}while(stt != ci);
prvi = r[fe] = t[stt] - alts;
if(prvi % 2) return cout << 0 << endl, 0;
ll pi = st.top(); st.pop();
while(!st.empty()){
ll sti = st.top(); st.pop();
for(pair<ll, ll> p : adj[sti]) if(e[p.s].f == pi || e[p.s].s == pi) {
prvi = r[p.s] = 2 * (t[pi] - prvi / 2);
if(prvi % 2) return cout << 0 << endl, 0;
}
pi = sti;
}
FOR(i, 1, m) cout << r[i] << endl;
}
