Submission #122965

#	Time	Username	Problem	Language	Result	Execution time	Memory
122965		SuperJava	Pipes (BOI13_pipes)	C++17	100 / 100	252 ms	36844 KiB

pipes

//fold
#ifndef KHALIL
#include <bits/stdc++.h>
#else
#include "header.h"
#endif
#define endl '\n'
#define mp make_pair
#define tostr(x) static_cast<ostringstream&>((ostringstream()<<dec<<x)).str()
#define rep(i,begin,end) for(auto i = begin;i < end;i++)
#define repr(i,begin,end) for(auto i = begin-1;i >= end;i--)
#define pb push_back
#define sz(a) ((int)(a).size())
#define fi first
#define se second
#define abs(a) ((a) < (0) ? (-1)*(a) : (a))
#define SQ(a) ((a)*(a))
#define eqd(a,b) (abs(a-b)<1e-9)
#define X real()
#define Y imag()
using namespace std;
typedef long long ll;
typedef long double ld;
template <typename t> t in(t q){cin >> q;return q;}
template <typename T> ostream& operator<<(ostream& os, const vector<T>& v){os << "[";for (int i = 0; i < sz(v); ++i) { os << v[i]; if (i != sz(v) - 1) os << ",";}os << "]";return os;}
template <typename T, typename S>ostream& operator<<(ostream& os, const map<T, S>& v){for (auto it : v)os << "(" << it.first << ":" << it.second << ")";return os;}
template <typename T, typename S>ostream& operator<<(ostream& os, const pair<T, S>& v){os << "(" << v.first << "," << v.second << ")";return os;}
const long double PI = acosl(-1);
mt19937 rng(chrono::steady_clock::now().time_since_epoch().count());
mt19937_64 rng64(chrono::steady_clock::now().time_since_epoch().count());
inline int rand(int l,int r){return uniform_int_distribution<int>(l, r)(rng);}
inline ll rand(ll l,ll r){return uniform_int_distribution<ll>(l, r)(rng64);}
//endfold
#define  N  (200'005)
#define MOD (1'000'000'007ll)
#define OO (1'050'000'000)
#define OOL (1'100'000'000'000'000'000ll)

//global
set<pair<ll,ll>> s;
set<pair<ll,ll>> adj[N];
ll sum[N];
ll val[N];

vector<ll> res;

void dfs(ll u,ll p){
	res.push_back(u);
	for(auto v:adj[u]){
		if(v.first != p && v.first != res[0]){
			dfs(v.first,u);
			return;
		}
	}
}

int main(){
	//fold
	ios::sync_with_stdio(0);
	cin.tie(0); cout.tie(0);
	cout << setprecision(10);
	//endfold
	ll n,m;
	cin >> n >> m;
	if(m > n) return cout << 0,0;
	rep(i,1,n+1){
		cin >> sum[i];
	}
	rep(i,0,m){
		ll u,v;
		cin >> u >> v;
		adj[u].insert({v,i});
		adj[v].insert({u,i});
	}
	rep(i,1,n+1){
		if(sz(adj[i])) s.insert({sz(adj[i]),i});
	}
	
	while(sz(s) && s.begin()->first == 1){
		ll u = s.begin()->second;
		s.erase(s.begin());
		ll v = adj[u].begin()->first;
		ll edgide = adj[u].begin()->second;
		s.erase({sz(adj[v]),v});
		adj[u].erase(adj[u].begin());
		adj[v].erase({u,edgide});
		val[edgide] = sum[u];
		sum[u] = 0;
		sum[v] -= val[edgide];
		if(sz(adj[v])) s.insert({sz(adj[v]),v});
	}
	if(sz(s) && s.begin()->first == 2){
		dfs(s.begin()->second,0);
		if(sz(res)%2 == 0) return cout << 0,0;
		ll ans = sum[res[0]];
		rep(i,1,sz(res)){
			if(i&1) ans += sum[res[i]];
			else ans -= sum[res[i]];
		}
		ans /= 2;
		ll u = res[0];
		s.erase({sz(adj[u]),u});
		ll v = res[1];
		ll edgide = (*adj[u].lower_bound({v,0})).second;
		s.erase({sz(adj[v]),v});
		adj[u].erase({v,edgide});
		adj[v].erase({u,edgide});
		val[edgide] = ans;
		sum[u] -= val[edgide];
		sum[v] -= val[edgide];
		if(sz(adj[v])) s.insert({sz(adj[v]),v});
	}
	while(sz(s) && s.begin()->first == 1){
		ll u = s.begin()->second;
		s.erase(s.begin());
		ll v = adj[u].begin()->first;
		ll edgide = adj[u].begin()->second;
		s.erase({sz(adj[v]),v});
		adj[u].erase(adj[u].begin());
		adj[v].erase({u,edgide});
		val[edgide] = sum[u];
		sum[u] = 0;
		sum[v] -= val[edgide];
		if(sz(adj[v])) s.insert({sz(adj[v]),v});
	}
	rep(i,0,m){
		cout << val[i]*2 << endl;
	}
	return 0;
}

• Subtask 1: 30 / 30
• Subtask 2: 70 / 70