| # | Time | Username | Problem | Language | Result | Execution time | Memory |
|---|---|---|---|---|---|---|---|
| 1077719 | TVSown | Pipes (BOI13_pipes) | C++17 | 0 ms | 0 KiB |
This submission is migrated from previous version of oj.uz, which used different machine for grading. This submission may have different result if resubmitted.
///*** Sown_Vipro ***///
/// ->TUYEN QUOC GIA<- ///
#include<bits/stdc++.h>
using namespace std;
//#pragma GCC optimize ("O3")
//#pragma GCC optimize ("unroll-loops")
//#pragma GCC target("popcnt")
#define F first
#define S second
#define pb push_back
#define pi pair<int, int>
#define pii pair<int, pair<int, int> >
#define all(a) a.begin(), a.end()
#define FOR(i, a, b) for(int i = a; i <= b; ++i)
#define REP(i, a, b) for(int i = a; i >= b; --i)
#define inp(name) if(fopen(name, "r")) freopen(name, "r", stdin);
#define out(name) if(fopen(name, "w")) freopen(name, "w", stdout);
#define szz(s) int(s.size())
#define int long long
const int N = 1e6 + 5, MAX = 1e6, oo = 1e9 + 5, MOD = 1e9 + 7;
int n, m;
int ans[N], c[N], deg[N];
vector<pi> e[N];
namespace sub1{
void dfs(int u, int p){
for(auto [v, i] : e[u]){
if(v == p) continue;
dfs(v, u);
ans[i] = 2 * c[v];
c[u] -= c[v];
}
}
void solve(){
dfs(1, 0);
FOR(i, 1, m) cout << ans[i] << "\n";
}
}
namespace sub2{
int vst[N], root, A, B;
vector<int> st;
queue<int> q;
void dfs(int u, int p, int type){
st.pb(u);
// cout << u << "\n";
vst[u] = 1;
if(type) A += c[u];
else B += c[u];
for(auto [v, i] : e[u]){
if(vst[v]) continue;
dfs(v, u, type ^ 1);
}
}
void solve(){
FOR(u, 1, n){
if(deg[u] == 1) q.push(u);
}
while(szz(q)){
int u = q.front(); q.pop();
vst[u] = 1;
for(auto [v, i] : e[u]){
if(vst[v]) continue;
ans[i] += 2 * c[u];
c[u] -= c[u];
c[v] -= c[u];
--deg[v];
if(deg[v] == 1){
q.push(v);
}
}
}
int cnt = 0;
FOR(u, 1, n){
// cout << c[u] << "\n";
if(!vst[u]){
// cout << u << "\n";
++cnt; root = u;
}
}
if(cnt % 2 == 0){
cout << 0; return;
}
dfs(root, 0, 1);
st.pb(root);
FOR(i, 0, szz(st) - 2){
int u = st[i];
for(auto [v, i] : e[u]){
if(v == st[i + 1]){
if(i % 2) ans[i] = B - A;
else ans[i] = A - B;
}
}
}
FOR(i, 1, n) cout << ans[i] << "\n";
}
}
void solve(){
cin >> n >> m;
FOR(u, 1, n) cin >> c[u];
FOR(i, 1, m){
int u, v; cin >> u >> v;
e[u].pb({v, i});
e[v].pb({u, i});
++deg[u];
++deg[v];
}
if(m == n - 1) sub1::solve();
else if(m > n) cout << 0;
else sub2::solve();
}
signed main(){
ios_base::sync_with_stdio(false);
cin.tie(0); cout.tie(0);
inp("in.txt");
int t = 1;
// cin >> t;
while(t--){
solve();
}
}