#include <bits/stdc++.h>
using namespace std;
const int MAXN = 1e5 + 11;
const int MAXM = 5e5 + 11;
struct edge{
int u, v, w;
int exc(int x){
return u + v - x;
}
};
vector<edge> E;
set<int> G[MAXN];
int a[MAXN], b[MAXN], c[MAXM];
int32_t main(){
cin.tie(0); cout.tie(0)->sync_with_stdio(false);
int n, m; cin >> n >> m;
for(int i = 1; i <= n; i++) cin >> a[i];
int s = accumulate(a + 1, a + n + 1, 0LL);
if(s % 2 == 1){
cout << 0 << endl;
return 0;
}
for(int i = 0; i < m; i++){
int u, v; cin >> u >> v;
E.push_back({u, v, 0});
G[u].insert(i);
G[v].insert(i);
}
vector<int> d1;
for(int i = 1; i <= n; i++){
if(G[i].size() == 1) d1.push_back(i);
}
while(!d1.empty()){
int v = d1.back(); d1.pop_back();
if(G[v].empty()) continue;
for(auto e : G[v]){
int u = E[e].u + E[e].v - v;
G[u].erase(e);
if(G[u].size() == 1) d1.push_back(u);
}
for(auto e : G[v]){
c[e] = (a[v] - b[v]) * 2;
b[E[e].u] += c[e] / 2;
b[E[e].v] += c[e] / 2;
}
G[v].clear();
}
int node = 0, x = -1;
for(int i = 1; i <= n; i++){
if(G[i].size() == 2){
node++; x = i;
}else if(G[i].size() > 2){
cout << 0 << endl;
return 0;
}
}
if(node > 0 && node % 2 == 0){
cout << 0 << endl;
return 0;
}
if(node >= 3){
vector<int> V, paths;
V.push_back(x); paths.push_back(*G[x].begin());
x = E[*G[x].begin()].u;
for(int i = 1; i < node; i++){
V.push_back(x); paths.push_back(E[*G[x].begin()].exc(x) == V[i - 1] ? *--G[x].end() : *G[x].begin());
x = E[paths.back()].exc(x);
}
vector<int> tmp; tmp.push_back(0); for(int i = 1; i < node; i++) tmp.push_back((a[V[i]] - b[V[i]]) * 2 - tmp.back());
int d = ((a[V[0]] - b[V[0]]) * 2 - tmp[0] - tmp[node - 1]) / 2;
tmp.clear(); tmp.push_back(d); for(int i = 1; i < node; i++) tmp.push_back((a[V[i]] - b[V[i]]) * 2 - tmp.back());
for(int i = 0; i < node; i++) c[paths[i]] = tmp[i];
}
for(int i = 0; i < m; i++){
cout << c[i] << '\n';
}
}
