/*input
3 3
9
4
6
1 2
2 3
3 1
7 7
2
2
2
2
2
2
2
1 2
2 3
3 4
4 5
5 6
6 7
7 1
*/
#include <bits/stdc++.h>
using namespace std;
typedef long long ll;
typedef long double ld;
typedef complex<ld> cd;
typedef pair<int, int> pi;
typedef pair<ll, ll> pl;
typedef pair<ld, ld> pd;
typedef vector<int> vi;
typedef vector<vi> vii;
typedef vector<ld> vd;
typedef vector<ll> vl;
typedef vector<vl> vll;
typedef vector<pi> vpi;
typedef vector<vpi> vpii;
typedef vector<pl> vpl;
typedef vector<cd> vcd;
typedef vector<pd> vpd;
typedef vector<bool> vb;
typedef vector<vb> vbb;
typedef std::string str;
typedef std::vector<str> vs;
#define x first
#define y second
#define debug(...) cout<<"["<<#__VA_ARGS__<<": "<<__VA_ARGS__<<"]\n"
const int MOD = 1000000007;
const ll INF = std::numeric_limits<ll>::max();
const int MX = 500101;
const ld PI = 3.14159265358979323846264338327950288419716939937510582097494L;
template<typename T>
pair<T, T> operator+(const pair<T, T> &a, const pair<T, T> &b) { return pair<T, T>(a.x + b.x, a.y + b.y); }
template<typename T>
pair<T, T> operator-(const pair<T, T> &a, const pair<T, T> &b) { return pair<T, T>(a.x - b.x, a.y - b.y); }
template<typename T>
T operator*(const pair<T, T> &a, const pair<T, T> &b) { return (a.x * b.x + a.y * b.y); }
template<typename T>
T operator^(const pair<T, T> &a, const pair<T, T> &b) { return (a.x * b.y - a.y * b.x); }
template<typename T>
void print(vector<T> vec, string name = "") {
cout << name;
for (auto u : vec)
cout << u << ' ';
cout << '\n';
}
vl W(MX);
int N, M;
vector<vpi> edges(MX);
vi sz(MX, 0);
vb done(MX, false);
vl ats(MX, -1);
void bad() {
printf("0\n");
exit(0);
}
vb visited(MX, false);
int cnt = 0;
void dfs(int v) {
cnt++;
visited[v] = true;
for (auto u : edges[v])
if (!visited[u.x] and !done[u.y])
dfs(u.x);
}
vi nodes;
vi edg;
int prad;
void dfs2(int v, int p) {
if (visited[v]) return;
nodes.push_back(v);
visited[v] = true;
for (auto u : edges[v]) {
if (!done[u.y] and u.x != p) {
edg.push_back(u.y);
dfs2(u.x, v);
break;
}
}
}
int main() {
ios_base::sync_with_stdio(0); cin.tie(0); cout.tie(0);
cin >> N >> M;
for (int i = 0; i < N; ++i)
cin >> W[i];
for (int i = 0; i < M; ++i)
{
int a, b;
cin >> a >> b; a--; b--;
sz[a]++;
sz[b]++;
edges[a].push_back({b, i});
edges[b].push_back({a, i});
}
queue<int> vienas;
for (int i = 0; i < N; ++i)
{
if (sz[i] == 1)
vienas.push(i);
}
while (vienas.size()) {
int c = vienas.front(); vienas.pop();
for (auto u : edges[c]) {
if (done[u.y]) continue;
sz[c]--;
sz[u.x]--;
done[u.y] = true;
ats[u.y] = 2 * W[c];
W[u.x] -= W[c];
if (sz[u.x] == 1)
vienas.push(u.x);
break;
}
}
bool visi2 = true;
for (int i = 0; i < N; ++i)
{
if (sz[i] != 2 and sz[i] != 0) {
visi2 = false;
break;
}
}
if (!visi2) bad();
for (int i = 0; i < N; ++i)
{
if (visited[i]) continue;
cnt = 0;
dfs(i);
if (cnt % 2 == 0) bad();
}
visited = vb(MX, false);
auto daryk = [&]() {
int K = (int)nodes.size();
ll visux = 0;
for (int i = 0; i < K; ++i)
visux += W[nodes[i]];
// printf("visux = %lld\n", visux);
ll curr = 0;
for (int i = 0; i < K; i += 2)
curr += 2 * W[nodes[i]];
for (int i = 0; i < K; i += 2)
{
curr -= 2 * W[nodes[i]];
ats[edg[i]] = visux - curr;
if (i + 1 < K)
curr += 2 * W[nodes[i + 1]];
}
curr = 0;
for (int i = 1; i < K; i += 2)
curr += 2 * W[nodes[i]];
for (int i = 1; i < K; i += 2)
{
curr += 2 * W[nodes[i - 1]];
curr -= 2 * W[nodes[i]];
ats[edg[i]] = visux - curr;
}
};
for (int i = 0; i < N; ++i)
{
if (!visited[i]) {
nodes.clear();
edg.clear();
dfs2(i, -1);
if ((int)nodes.size() == 1) continue;
// print(nodes);
daryk();
}
}
for (int i = 0; i < M; ++i)
printf("%lld\n", ats[i]);
}
/* Look for:
* special cases (n=1?)
* overflow (ll vs int?)
* the exact constraints (multiple sets are too slow for n=10^6 :( )
* array bounds
*/
