Submission #319029

# Submission time Handle Problem Language Result Execution time Memory
319029 2020-11-03T18:34:47 Z rqi Pipes (BOI13_pipes) C++14
100 / 100
386 ms 19556 KB
#include <bits/stdc++.h>

using namespace std;

typedef vector<int> vi;
typedef long long ll;
typedef pair<int, int> pi;
typedef vector<pi> vpi;

#define mp make_pair
#define f first
#define s second
#define pb push_back

struct DSU{
	vi e;
	void init(int n){
		e = vi(n, -1);
	}
	int get(int a){
		if(e[a] < 0) return a;
		e[a] = get(e[a]);
		return e[a];
	}
	bool unite(int a, int b){
		a = get(a);
		b = get(b);
		if(a == b) return 0;
		if(-e[a] < -e[b]) swap(a, b);
		e[b] = a;
		return 1;
	}
};

const int mx = 500005;
const int mx1 = 100005;
int N, M;
ll c[mx1];
ll origc[mx1];
int u[mx];
int v[mx];
ll x[mx];

bool inTree[mx1];
vpi adj[mx1];

int depth[mx1];

void genTree(int node, int prv = -1, int d = 0){
	depth[node] = d;
	for(auto u: adj[node]){
		if(u.f == prv) continue;
		genTree(u.f, node, d+1);
		ll val = c[u.f];
		x[u.s]+=val;
		c[u.f]-=val;
		c[node]-=val;
	}
}

int main(){
	cin >> N >> M;
	DSU dsu;
	dsu.init(N+5);
	for(int i = 1; i <= N; i++){
		cin >> c[i];
		origc[i] = c[i];
	}
	for(int i = 1; i <= M; i++){
		cin >> u[i] >> v[i];
		if(dsu.unite(u[i], v[i])){
			inTree[i] = 1;
			adj[u[i]].pb(mp(v[i], i));
			adj[v[i]].pb(mp(u[i], i));
		}
	}

	genTree(1);

	if(M == N-1){ //Good
		if(c[1] != 0){
			assert(0==1);
			cout << 0 << "\n";
			return 0;
		}
		for(int i = 1; i <= M; i++){
			cout << 2*x[i] << "\n";
		}
		return 0;
	}

	if(M >= N+1){
		cout << 0 << "\n";
		return 0;
	}

	for(int i = 1; i <= M; i++){
		if(inTree[i]) continue;
		if(depth[u[i]] % 2 != depth[v[i]] % 2){
			cout << 0 << "\n";
			return 0;
		}
		for(int j = 1; j <= M; j++){
			x[j] = 0;
		}
		if(depth[u[i]] % 2 == 0) x[i] = c[1]/2;
		else x[i] = -c[1]/2;
		for(int j = 1; j <= N; j++){
			c[j] = origc[j];
		}
		c[u[i]]-=x[i];
		c[v[i]]-=x[i];
		genTree(1);
		assert(c[1] == 0);
	}


	for(int i = 1; i <= M; i++){
		cout << 2*x[i] << "\n";
	}

}
# Verdict Execution time Memory Grader output
1 Correct 2 ms 2668 KB Output is correct
2 Correct 2 ms 2668 KB Output is correct
3 Correct 3 ms 2796 KB Output is correct
4 Correct 135 ms 11492 KB Output is correct
5 Correct 2 ms 2668 KB Output is correct
6 Correct 2 ms 2668 KB Output is correct
7 Correct 2 ms 2668 KB Output is correct
8 Correct 2 ms 2668 KB Output is correct
9 Correct 3 ms 2796 KB Output is correct
10 Correct 3 ms 2796 KB Output is correct
11 Correct 3 ms 2796 KB Output is correct
12 Correct 3 ms 2796 KB Output is correct
13 Correct 110 ms 10340 KB Output is correct
14 Correct 131 ms 11748 KB Output is correct
15 Correct 154 ms 12188 KB Output is correct
16 Correct 113 ms 10980 KB Output is correct
17 Correct 139 ms 12132 KB Output is correct
18 Correct 147 ms 12260 KB Output is correct
19 Correct 145 ms 16228 KB Output is correct
20 Correct 2 ms 2668 KB Output is correct
21 Correct 3 ms 2796 KB Output is correct
22 Correct 140 ms 12132 KB Output is correct
23 Correct 109 ms 10468 KB Output is correct
24 Correct 142 ms 12260 KB Output is correct
25 Correct 113 ms 10852 KB Output is correct
# Verdict Execution time Memory Grader output
1 Correct 2 ms 2668 KB Output is correct
2 Correct 3 ms 2924 KB Output is correct
3 Correct 127 ms 13796 KB Output is correct
4 Correct 128 ms 14620 KB Output is correct
5 Correct 119 ms 11492 KB Output is correct
6 Correct 386 ms 19432 KB Output is correct
7 Correct 2 ms 2668 KB Output is correct
8 Correct 2 ms 2668 KB Output is correct
9 Correct 2 ms 2668 KB Output is correct
10 Correct 2 ms 2668 KB Output is correct
11 Correct 2 ms 2668 KB Output is correct
12 Correct 2 ms 2668 KB Output is correct
13 Correct 3 ms 2668 KB Output is correct
14 Correct 2 ms 2668 KB Output is correct
15 Correct 3 ms 2924 KB Output is correct
16 Correct 3 ms 2796 KB Output is correct
17 Correct 3 ms 2796 KB Output is correct
18 Correct 3 ms 2796 KB Output is correct
19 Correct 3 ms 2796 KB Output is correct
20 Correct 3 ms 2792 KB Output is correct
21 Correct 4 ms 2796 KB Output is correct
22 Correct 4 ms 2796 KB Output is correct
23 Correct 133 ms 13496 KB Output is correct
24 Correct 161 ms 15880 KB Output is correct
25 Correct 127 ms 14004 KB Output is correct
26 Correct 132 ms 17252 KB Output is correct
27 Correct 137 ms 17764 KB Output is correct
28 Correct 128 ms 12004 KB Output is correct
29 Correct 319 ms 18736 KB Output is correct
30 Correct 157 ms 19372 KB Output is correct
31 Correct 198 ms 18788 KB Output is correct
32 Correct 161 ms 13540 KB Output is correct
33 Correct 140 ms 15340 KB Output is correct
34 Correct 134 ms 16740 KB Output is correct
35 Correct 133 ms 14820 KB Output is correct
36 Correct 133 ms 11876 KB Output is correct
37 Correct 376 ms 19556 KB Output is correct
38 Correct 155 ms 15336 KB Output is correct
39 Correct 152 ms 13144 KB Output is correct
40 Correct 175 ms 15252 KB Output is correct
41 Correct 137 ms 18788 KB Output is correct
42 Correct 135 ms 18916 KB Output is correct
43 Correct 132 ms 16352 KB Output is correct
44 Correct 125 ms 11748 KB Output is correct
45 Correct 323 ms 14948 KB Output is correct
46 Correct 171 ms 17636 KB Output is correct
47 Correct 167 ms 15576 KB Output is correct
48 Correct 154 ms 19556 KB Output is correct
49 Correct 122 ms 12772 KB Output is correct
50 Correct 136 ms 15960 KB Output is correct
51 Correct 132 ms 13796 KB Output is correct
52 Correct 130 ms 13016 KB Output is correct
53 Correct 313 ms 16484 KB Output is correct
54 Correct 155 ms 16868 KB Output is correct