2 1
1 1
2 1
 8 12
-6 2 -3 2 6 -7 1 -5
2 1
5 6
1 6
1 4
8 2
2 7
2 5
8 3
8 4
3 7
7 6
3 1
 10 13
3 4 -3 8 6 4 -5 1 3 -7
9 5
9 2
10 3
1 4
3 5
9 1
6 10
10 4
3 1
2 7
1 6
1 7
7 8
 43 52
-23 -18 -35 21 -12 38 -35 -11 28 -20 27 -5 9 -19 -39 -25 -32 32 -36 28 11 37 1 -25 -22 9 -15 21 25 -39 10 36 -30 -40 22 26 25 -27 -22 -38 -1 18 -13
33 40
31 23
30 26
21 17
6 2
41 19
32 39
32 23
13 14
25 35
31 30
19 32
25 22
34 36
7 40
23 6
40 12
1 3
23 43
36 13
18 33
17 32
7 3
21 34
41 35
20 7
23 1
41 8
25 19
20 29
42 5
40 21
9 37
17 41
30 10
41 18
39 1
20 24
20 4
42 3
20 25
5 16
31 9
42 28
10 11
19 42
31 38
25 2
31 27
17 25
13 15
31 20
 2 1
1 1
1 2
 5 7
4 1 5 3 -1
2 4
5 4
5 2
1 5
1 2
4 1
1 3
 10 12
5 1 1 8 -8 10 -3 -2 1 7
5 3
8 2
10 9
4 6
5 6
4 5
5 10
4 7
8 4
3 1
3 6
6 10
 20 40
-9 -10 -9 15 -3 -5 -17 -10 -6 2 -13 19 10 -15 15 -14 17 0 7 -8
3 17
6 18
15 12
2 5
18 3
16 20
6 17
20 10
10 18
9 12
15 3
6 4
15 16
20 6
20 9
9 4
4 8
14 5
11 7
12 11
3 13
14 19
7 17
16 14
19 7
12 13
14 13
13 11
9 14
13 17
8 19
5 20
2 17
2 16
12 5
8 1
20 3
6 2
5 18
13 8

YES
                                                               1
 NO
 YES
                                                              -7
                                                              10
                                                             -16
                                                               3
                                                              13
                                                               0
                                                               4
                                                               5
                                                               0
                                                              -6
                                                               0
                                                               0
                                                               1
 NO
 YES
                                                               1
 YES
                                                               2
                                                               1
                                                              -1
                                                              -1
                                                               0
                                                               0
                                                               5
 YES
-4
1
1
17
-7
-3
6
-3
-3
5
0
0
 YES
                                                             -30
                                                             -21
                                                             -23
                                                             -10
                                                              21
                                                             -52
                                                               0
                                                               2
                                                               0
                                                              -9
                                                               0
                                                              16
                                                              38
                                                               0
                                                              42
                                                               0
                                                              -1
                                                               7
                                                             -64
                                                              51
                                                               0
                                                               7
                                                              47
                                                               0
                                                               0
                                                               0
                                                              10
                                                               0
                                                             -39
                                                               0
                                                               0
                                                               0
                                                               0
                                                               0
                                                               0
                                                              -9
                                                               0
                                                               0
                                                               0
                                                               0

#include <bits/stdc++.h>
using namespace std;
const int MAXN = (int)1e6 + 3;
const int infint = (int)1e9 + 3;
const int MOD = (int)1e9 + 7;
const long long inf = (long long)1e18 + 3;
int n, m, c[MAXN], par[MAXN], visited[MAXN], h[MAXN], edge_1[MAXN],
    edge_2[MAXN];
map<pair<int, int>, int> M;
vector<int> G[MAXN];
void bfs(int u) {
  queue<int> q;
  q.push(u);
  visited[u] = 1;
  while (!q.empty()) {
    int st = q.front();
    q.pop();
    for (auto v : G[st])
      if (!visited[v]) par[v] = st, visited[v] = 1, h[v] = h[st] + 1, q.push(v);
  }
}
int dfs(int u) {
  int ans = 0;
  for (auto v : G[u])
    if (!visited[v]) visited[v] = 1, M[{u, v}] = dfs(v), ans += M[{u, v}];
  return c[u] - ans;
}
int main() {
  ios::sync_with_stdio(false);
  cin.tie(0);
  cout.tie(0);
  cin >> n >> m;
  for (int i = 1; i <= n; i++) cin >> c[i];
  for (int i = 0; i < m; i++) {
    int u, v;
    cin >> u >> v;
    edge_1[i] = u, edge_2[i] = v;
    G[u].push_back(v);
    G[v].push_back(u);
  }
  bfs(1);
  int a = -1, b = -1;
  for (int i = 1; i <= n; i++)
    for (auto u : G[i])
      if (h[i] == h[u]) a = i, b = u;
  if (a != -1) {
    vector<int> cyc;
    int lca = -1, tmp_a = a, tmp_b = b;
    while (a != b) {
      if (h[a] > h[b])
        a = par[a];
      else
        b = par[b];
    }
    lca = a;
    a = tmp_a, b = tmp_b;
    while (a != lca) {
      cyc.push_back(a);
      a = par[a];
    }
    vector<int> sec;
    while (b != lca) {
      sec.push_back(b);
      b = par[b];
    }
    reverse(sec.begin(), sec.end());
    cyc.push_back(lca);
    for (auto u : sec) cyc.push_back(u);
    for (auto u : cyc) cout << u << " ";
    cout << "\n";
    memset(visited, 0, sizeof visited);
    for (auto u : cyc) visited[u] = 1;
    for (auto u : cyc) c[u] = dfs(u);
    int ans = 0;
    for (int i = 0; i < (int)cyc.size(); i++)
      if (i <= 1)
        ans += c[cyc[i]];
      else if (i % 2 == 0)
        ans -= c[cyc[i]];
      else
        ans += c[cyc[i]];
    M[{cyc[0], cyc[1]}] = ans / 2;
    for (int i = 1; i < (int)cyc.size(); i++)
      ans = ans * -1 + 2 * c[cyc[i]],
      M[{cyc[i], cyc[(i + 1) % (int)cyc.size()]}] = ans / 2;
    cout << "YES\n";
    for (int i = 0; i < m; i++)
      cout << M[{edge_1[i], edge_2[i]}] + M[{edge_2[i], edge_1[i]}] << "\n";
    return 0;
  }
  memset(visited, 0, sizeof visited);
  visited[1] = 1;
  int x = dfs(1);
  if (x) return cout << "NO", 0;
  cout << "YES\n";
  for (int i = 0; i < m; i++)
    cout << M[{edge_1[i], edge_2[i]}] + M[{edge_2[i], edge_1[i]}] << "\n";
}
