Submission #94373

#	Time	Username	Problem	Language	Result	Execution time	Memory
94373		gumball	Pipes (BOI13_pipes)	C++14	74.07 / 100	139 ms	16820 KiB

pipes

#include<bits/stdc++.h>
#define ll long long
#define pb push_back
#define mp make_pair
#define fi first
#define se second
using namespace std;
ll n,m,i,a[101010],h[505050],ta,tb;
vector<ll> v[101010],w[101010];
ll dfs(ll aa,ll bb,ll cc)
{
	ll ii;
	for(ii=0;ii<v[aa].size();ii++)
	{
		if(w[aa][ii]==bb)continue;
		dfs(v[aa][ii],w[aa][ii],aa);
	}
	if(aa==1)
	{
		if(a[aa]!=0)
		{
			cout<<0<<"\n";
			exit(0);
		}
	}
	else
	{
		h[bb]=a[aa]*2;
		a[cc]-=a[aa];
		a[aa]-=0;
	}
}
int main()
{
	ios_base::sync_with_stdio(NULL);cin.tie(NULL);cout.tie(NULL);
	cin>>n>>m;
	if(m>=n)
	{
		cout<<0<<"\n";
		return 0;
	}
	for(i=1;i<=n;i++)cin>>a[i];
	for(i=1;i<=m;i++)
	{
		cin>>ta>>tb;
		v[ta].pb(tb);
		v[tb].pb(ta);
		w[ta].pb(i);
		w[tb].pb(i);
	}
	dfs(1,0,0);
	for(i=1;i<=m;i++)cout<<h[i]<<"\n";
}

Compilation message (stderr)

pipes.cpp: In function 'long long int dfs(long long int, long long int, long long int)':
pipes.cpp:13:13: warning: comparison between signed and unsigned integer expressions [-Wsign-compare]
  for(ii=0;ii<v[aa].size();ii++)
           ~~^~~~~~~~~~~~~
pipes.cpp:32:1: warning: control reaches end of non-void function [-Wreturn-type]
 }
 ^

• Subtask 1: 30 / 30
• Subtask 2: 44.074074074074076 / 70