#include <iostream>
#include <vector>
#include <queue>
using namespace std;
using ll = long long;
using vi = vector<int>;
using pii = pair<int, int>;
using vpii = vector<pii>;
using vll = vector<ll>;
#define sz(x) int(x.size())
const int mx = 100'000;
int N, M;
vpii edge[1+mx];
vll c(1+mx);
vll x(1+mx);
void dfs(int u, int p)
{
for(pii vp : edge[u])
{
int v = vp.first;
int e = vp.second;
if(v == p) continue;
dfs(v, u);
x[e] = 2*c[v];
c[u] -= c[v];
c[v] = 0;
}
}
int main()
{
ios_base::sync_with_stdio(false);
cin.tie(NULL);
int N, M;
cin >> N >> M;
if(M > N)
{
cout << "0\n";
return 0;
}
for(int i = 1; i <= N; i++) cin >> c[i];
for(int j = 1; j <= M; j++)
{
int u, v;
cin >> u >> v;
edge[u].push_back({v, j});
edge[v].push_back({u, j});
}
if(M == N-1)
{
dfs(1, 0);
}
else
{
queue<int> tbv;
vi visit(1+N, 0);
vi deg(1+N);
for(int i = 1; i <= N; i++)
{
deg[i] = sz(edge[i]);
if(deg[i] == 1)
{
tbv.push(i);
visit[i] = 1;
}
}
cerr << "A\n";
while(!tbv.empty())
{
int u = tbv.front();
tbv.pop();
for(auto vp : edge[u])
{
int v = vp.first;
int e = vp.second;
if(visit[v]) continue;
deg[v]--;
x[e] = 2*c[v];
c[v] -= c[u];
c[u] = 0;
if(!deg[v])
{
tbv.push(v);
visit[v] = 1;
}
}
}
cerr << "B\n";
int U = 1;
while(visit[U])
U++;
int viscount = 0;
for(int u = 1; u <= N; u++)
viscount += visit[u];
vi edgevis(1+N, 0);
cerr << "C\n";
vi nodes, edges;
for(int z = 1; z <= N - viscount; z++)
{
for(auto vp : edge[U])
{
int v = vp.first;
int e = vp.second;
if(visit[v]) continue;
if(edgevis[e]) continue;
edgevis[e] = 1;
nodes.push_back(U);
edges.push_back(e);
U = v;
}
}
// cerr << "D\n";
int Z = N - viscount;
// cerr << "Z = " << Z << '\n';
// for(int z = 0; z < Z; z++) cerr << nodes[z] << ' ' << edges[z] << '\n';
if(Z % 2 == 0)
{
cout << "0\n";
return 0;
}
vll a(Z), b(Z);
a[0] = 1;
b[0] = 0;
for(int i = 1; i < Z; i++)
{
a[i] = -a[i-1];
b[i] = c[nodes[i]] - b[i-1];
}
//(a.back() + a[0]) * x + (b.back() + b[0]) == c[nodes[0]]
//x = (c[nodes[0]] - (b.back() + b[0])) / (a.back() + a[0])
for(int i = 0; i < Z; i++)
{
x[edges[i]] = -((a[i] * (c[nodes[0]] - (b.back() + b[0]))) / (a.back() + a[0]) + b[i])
}
}
for(int e = 1; e <= M; e++)
cout << x[e] << '\n';
}
Compilation message
pipes.cpp: In function 'int main()':
pipes.cpp:175:90: error: expected ';' before '}' token
175 | x[edges[i]] = -((a[i] * (c[nodes[0]] - (b.back() + b[0]))) / (a.back() + a[0]) + b[i])
| ^
| ;
176 | }
| ~