#include <bits/stdc++.h>
#define int long long
using namespace std;
#define pii pair<int,int>
#define f first
#define s second
const int N = 5e5+5;
set<int> A[N];
pii e[N];
int c[N],ans[N],deg[N];
int n,m,a,b;
int get_node(int u,int i) {
int adj_edge = (i == 0?*A[u].begin() : *A[u].rbegin());
int adj_node = e[i].f^e[i].s^u;
return adj_node;
}
void dfs(int u,int p, int root,vector<pii> &order) {
int nxt;
nxt = get_node(u,0);
if(nxt!=p){
order.push_back({u,*A[u].begin()});
} else {
nxt = get_node(u,1);
if(nxt!=p)order.push_back({u,*A[u].rbegin()});
}
if(nxt!=root)dfs(nxt,u,root,order);
}
int32_t main(){
cin>>n>>m;
for(int i = 1;i<=n;i++)cin>>c[i];
for(int i = 1;i<=m;i++) {
cin>>a>>b;
A[a].insert(i);
A[b].insert(i);
deg[a]++,deg[b]++;
e[i] = {a,b};
}
queue<int> q;
for(int i = 1;i<=n;i++) q.push(i);
while(!q.empty()) {
int cur = q.front(); q.pop();
if(A[cur].size() == 1) {
int adj_edge = *A[cur].begin();
int adj_node = (e[adj_edge].f==cur?e[adj_edge].s : e[adj_edge].f);
ans[adj_edge] = 2LL * c[cur];
c[cur] -= ans[adj_edge]/2LL;
c[adj_node] -= ans[adj_edge]/2LL;
A[cur].erase(adj_edge);
A[adj_node].erase(adj_edge);
if(A[adj_node].size() == 1) q.push(adj_node);
}
}
//check for more than 3 or odd cycle
int cnt = 0;
for(int i = 1;i<=n;i++) {
if(A[i].size() > 2) {
cout << 0;
return 0;
}
cnt += A[i].size() == 2;
}
if(cnt > 0 && cnt % 2 == 0) {
cout << 0;
return 0;
}
int st = 0;
for(st = 1;st<=n;st++){
if(A[st].size()==2){
break;
}
}
if(st<=n) {
vector<pii> order;
dfs(st, -1, st, order);
int sus = 2LL * c[st];
int diff = 0;
for(int i = 0;i<order.size();i++) {
diff = 2LL * c[order[i].f] - diff;
}
ans[order[0].s] = (sus - diff) / 2LL;
for(int i = 1;i<order.size();i++) ans[order[i].s] = 2LL * c[order[i].f] - ans[order[i-1].s];
}
for(int i = 1;i<=m;i++)cout<<ans[i]<<"\n";
}
/*
one edge = uniquely determines the edge weight
cycles can be unique if there are no arbitrary in/outflows
check for unique determination of weights
then check for cycle and cycle validity
1) check for unique determinants and propagate them
2) check for cycle
so many tricks
- check for double odd cycle using deg >= 3
- insert edge id and not pair
- set instead of vec
*/
