Submission #243285

#	Submission time	Handle	Problem	Language	Result	Execution time	Memory
243285	2020-06-30T19:33:58 Z	anubhavdhar	Pipes (BOI13_pipes)	C++14	100 / 100	470 ms	31892 KB

pipes

#include<bits/stdc++.h>

#define ll long long int
#define pb push_back
#define mp make_pair
#define FOR(i,n) for(i=0;i<(n);++i)
#define FORe(i,n) for(i=1;i<=(n);++i)
#define FORr(i,a,b) for(i=(a);i<(b);++i)
#define FORrev(i,n) for(i=(n);i>=0;--i)
#define F0R(i,n) for(int i=0;i<(n);++i)
#define F0Re(i,n) for(int i=1;i<=(n);++i)
#define F0Rr(i,a,b) for(ll i=(a);i<(b);++i)
#define F0Rrev(i,n) for(int i=(n);i>=0;--i)
#define ii pair<ll,ll>
#define vi vector<ll>
#define vii vector<ii>
#define ff first 
#define ss second
#define cd complex<double>
#define vcd vector<cd>
#define ldd long double
#define dbgLine cout<<"Line : "<<__LINE__<<'\n'
#define all(x) (x).begin(),(x).end()

using namespace std;

const short int __PRECISION = 10;

const ll MOD = 1e9+7;
const ll INF = 1e17 + 1101;
const ll LOGN = 17;
const ll MAXN = 2e5+5;
const ll ROOTN = 320;
 
const ldd PI = acos(-1);
const ldd EPS = 1e-7;

int N, M;

int main()
{
	/*
	ios_base::sync_with_stdio(false);
	cin.tie(NULL);
	cout.tie(NULL);
	*/
	cin>>N>>M;
	if(M > N)
	{
		puts("0");
		exit(0);
	}
	ll c[N+1], sum = 0;
	int dep[N+1], weight[M+1], par[N+1], j, k;
	bool vis[N+1];
	set<pair<int, int>> g[N+1];
	F0Re(i, N)
		cin>>c[i], vis[i] = false, sum += c[i];
	sum /= 2;
	map<pair<int, int>, int> index;
	F0R(i, M)
	{
		cin>>j>>k;
		g[j].insert(mp(k, i));
		g[k].insert(mp(j, i));
		index[mp(j, k)] = index[mp(k, j)] = i;
	}

	// dbgLine;

	dep[1] = 0;
	vis[1] = true;
	par[1] = -1;
	queue<int> Q;
	Q.push(1);

	while(!Q.empty())
	{
		int a = Q.front();
		Q.pop();
		for(pair<int, int> p : g[a])
		{
			if(vis[p.ff] and dep[p.ff] != dep[a] and p.ff != par[a])
			{
				puts("0");
				exit(0);
			}
			if(!vis[p.ff])
			{
				vis[p.ff] = true;
				dep[p.ff] = dep[a] + 1;
				Q.push(p.ff);
				par[p.ff] = a;
			}
		}
	}

	// dbgLine;

	set<int> assigned;

	F0Re(i, N)
		if(g[i].size() == 1)
			Q.push(i);
	
	// dbgLine;

	while(!Q.empty())
	{
		int a = Q.front();
		Q.pop();
		if(g[a].size() == 0)
			continue;
		int b = g[a].begin()->ff, i = g[a].begin()->ss;
		// cout<<"in for a  = "<<a<<" and b = "<<b<<endl;
		g[a].erase(mp(b, i));
		if(g[b].size() == 0)
			continue;
		g[b].erase(mp(a, i));
		weight[i] = c[a];
		c[b] -= c[a];
		sum -= c[a];
		// dbgLine;
		assigned.insert(i);
		if(g[b].size() == 1)
			Q.push(b);
		// dbgLine;
	}

	// dbgLine;

	int cycle_size = M - assigned.size();

	// cout<<cycle_size<<endl;
	if(cycle_size)
	{
		int node, next[N+1], pre[N+1], tmp = 0;
		F0Re(i, N)
			next[i] = -1, pre[i] = -1;
		F0Re(i, N)
			if(g[i].size() != 0)
				{
					node = i;
					break;
				}
		next[node] = g[node].begin()->ff;
		pre[g[node].begin()->ff] = node;
		node = next[node];
		while(next[node] == -1)
			next[node] = g[node].begin()->ff + g[node].rbegin()->ff - pre[node]/*, cout<<"set next["<<node<<"] = "<<next[node]<<'\n'*/,
			 pre[next[node]] = node, node = next[node];
		F0R(i, cycle_size/2 + 1)
			node = next[next[node]], tmp += c[node];
		F0R(i, cycle_size)
		{
			weight[index[mp(node,next[node])]] = tmp - sum;
			tmp += c[next[next[node]]] - c[next[node]];
			node = next[next[node]];
		}
	}

	// dbgLine;

	F0R(i, M)
		cout<<2*weight[i]<<'\n';

	return 0;
}

Compilation message

pipes.cpp: In function 'int main()':
pipes.cpp:137:7: warning: 'node' may be used uninitialized in this function [-Wmaybe-uninitialized]
   int node, next[N+1], pre[N+1], tmp = 0;
       ^~~~

Subtask #1

30.0 / 30.0

#	Verdict	Execution time	Memory	Grader output
1	Correct	5 ms	384 KB	Output is correct
2	Correct	5 ms	384 KB	Output is correct
3	Correct	7 ms	640 KB	Output is correct
4	Correct	407 ms	31128 KB	Output is correct
5	Correct	5 ms	384 KB	Output is correct
6	Correct	5 ms	384 KB	Output is correct
7	Correct	5 ms	384 KB	Output is correct
8	Correct	5 ms	384 KB	Output is correct
9	Correct	6 ms	640 KB	Output is correct
10	Correct	7 ms	640 KB	Output is correct
11	Correct	7 ms	640 KB	Output is correct
12	Correct	7 ms	640 KB	Output is correct
13	Correct	385 ms	24828 KB	Output is correct
14	Correct	384 ms	29432 KB	Output is correct
15	Correct	388 ms	31168 KB	Output is correct
16	Correct	331 ms	26604 KB	Output is correct
17	Correct	389 ms	31024 KB	Output is correct
18	Correct	406 ms	31304 KB	Output is correct
19	Correct	366 ms	30968 KB	Output is correct
20	Correct	5 ms	384 KB	Output is correct
21	Correct	6 ms	640 KB	Output is correct
22	Correct	389 ms	31172 KB	Output is correct
23	Correct	308 ms	24824 KB	Output is correct
24	Correct	470 ms	31224 KB	Output is correct
25	Correct	333 ms	26044 KB	Output is correct

Subtask #2

70.0 / 70.0

#	Verdict	Execution time	Memory	Grader output
1	Correct	5 ms	384 KB	Output is correct
2	Correct	6 ms	640 KB	Output is correct
3	Correct	234 ms	28408 KB	Output is correct
4	Correct	5 ms	384 KB	Output is correct
5	Correct	5 ms	512 KB	Output is correct
6	Correct	5 ms	384 KB	Output is correct
7	Correct	5 ms	384 KB	Output is correct
8	Correct	5 ms	384 KB	Output is correct
9	Correct	5 ms	384 KB	Output is correct
10	Correct	5 ms	256 KB	Output is correct
11	Correct	5 ms	384 KB	Output is correct
12	Correct	5 ms	256 KB	Output is correct
13	Correct	5 ms	256 KB	Output is correct
14	Correct	5 ms	384 KB	Output is correct
15	Correct	7 ms	640 KB	Output is correct
16	Correct	6 ms	640 KB	Output is correct
17	Correct	6 ms	640 KB	Output is correct
18	Correct	5 ms	384 KB	Output is correct
19	Correct	5 ms	256 KB	Output is correct
20	Correct	5 ms	384 KB	Output is correct
21	Correct	5 ms	384 KB	Output is correct
22	Correct	7 ms	640 KB	Output is correct
23	Correct	348 ms	25976 KB	Output is correct
24	Correct	450 ms	31864 KB	Output is correct
25	Correct	245 ms	28536 KB	Output is correct
26	Correct	5 ms	384 KB	Output is correct
27	Correct	4 ms	384 KB	Output is correct
28	Correct	5 ms	384 KB	Output is correct
29	Correct	4 ms	384 KB	Output is correct
30	Correct	394 ms	31224 KB	Output is correct
31	Correct	390 ms	31736 KB	Output is correct
32	Correct	408 ms	31868 KB	Output is correct
33	Correct	267 ms	30204 KB	Output is correct
34	Correct	5 ms	384 KB	Output is correct
35	Correct	4 ms	384 KB	Output is correct
36	Correct	5 ms	384 KB	Output is correct
37	Correct	5 ms	384 KB	Output is correct
38	Correct	384 ms	31864 KB	Output is correct
39	Correct	397 ms	31864 KB	Output is correct
40	Correct	392 ms	31864 KB	Output is correct
41	Correct	268 ms	30076 KB	Output is correct
42	Correct	5 ms	384 KB	Output is correct
43	Correct	5 ms	384 KB	Output is correct
44	Correct	4 ms	384 KB	Output is correct
45	Correct	5 ms	384 KB	Output is correct
46	Correct	386 ms	31868 KB	Output is correct
47	Correct	425 ms	31892 KB	Output is correct
48	Correct	406 ms	31864 KB	Output is correct
49	Correct	259 ms	28404 KB	Output is correct
50	Correct	4 ms	384 KB	Output is correct
51	Correct	4 ms	384 KB	Output is correct
52	Correct	5 ms	432 KB	Output is correct
53	Correct	5 ms	384 KB	Output is correct
54	Correct	382 ms	31480 KB	Output is correct