#include <bits/stdc++.h>
#define ll long long
#define sz(x) (int)(x).size()
#define pii pair<int,int>
#define f first
#define s second
using namespace std;
const int MAXN=1e5+10;
int n,m,o;
vector<pii> edges[MAXN];
int scores[MAXN], cur[MAXN], ans[5*MAXN], counter[MAXN];
bool done[MAXN];
void dfsTree(int c, int p, int x)
{
for (pii i : edges[c])
if (i.f!=p)
{
dfsTree(i.f,c,i.s);
cur[c]+=ans[i.s];
}
if (c!=1)
{
ans[x]=scores[c]-cur[c];
cur[c]+=ans[x];
}
}
void treeCase()
{
dfsTree(1,0,0);
if (scores[1]!=cur[1])
{
cout<<0;
return;
}
for (int i=0;i<m;++i)
cout<<ans[i]*2<<"\n";
}
vector<int> circle;
vector<int> vals;
void dfs(int c, int p)
{
circle.push_back(c);
done[c]=1;
for (pii i : edges[c])
if (i.f!=p)
{
if (i.f==o)
{
vals.push_back(i.s);
return;
}
if (!done[i.f])
{
vals.push_back(i.s);
dfs(i.f,c);
}
}
}
int main()
{
ios_base::sync_with_stdio(0); cin.tie(0);
int u,v,x=0;
cin>>n>>m;
for (int i=1;i<=n;++i)
cin>>scores[i];
for (int i=0;i<m;++i)
{
cin>>u>>v;
edges[u].push_back({v,i});
edges[v].push_back({u,i});
}
if (m==n-1)
{
treeCase();
return 0;
}
if (m>n)
{
cout<<0;
return 0;
}
stack<int> st;
for (int i=1;i<=n;++i)
{
counter[i]=sz(edges[i]);
if (counter[i]==1)
st.push(i);
}
while (sz(st))
{
++x;
v=st.top();st.pop();
done[v]=1;
for (pii i : edges[v])
if (!done[i.f])
{
u=i.s;
ans[u]=scores[v]-cur[v];
cur[v]+=ans[u];
cur[i.f]+=ans[u];
--counter[i.f];
if (counter[i.f]==1)
st.push(i.f);
}
}
if ((n-x+1)&1)
{
cout<<0;
return 0;
}
for (int i=1;i<=n;++i)
if (!done[i])
{
o=i;
dfs(o,0);
break;
}
ll tot=0;
for (int i=0;i<n-x;++i)
{
if (i&1)
tot-=(scores[i]-cur[i]);
else
tot+=(scores[i]-cur[i]);
}
if (tot&1)
{
cout<<0;
return 0;
}
ans[vals.back()]=(tot>>1);
ans[vals[0]]=scores[circle[0]]-cur[circle[0]]-ans[vals.back()];
for (int i=1;i+1<n-x;++i)
ans[vals[i]]=scores[circle[i]]-cur[circle[i]]-ans[vals[i-1]];
if (scores[circle[0]]!=ans[vals[0]]+ans[vals.back()])
{
cout<<0;
return 0;
}
for (int i=1;i<n;++i)
{
if (scores[circle[i]]!=ans[vals[i]]+ans[vals[i-1]])
{
cout<<0;
return 0;
}
}
for (int i=0;i<m;++i)
cout<<ans[i]*2<<"\n";
return 0;
}
