oj.uz

Submission #33484

# Submission time Handle Problem Language Result Execution time Memory
33484 2017-10-27T14:36:33 Z szawinis Beads and wires (APIO14_beads) C++14
100 / 100
 242 ms 29300 KB 
#include <bits/stdc++.h>
using namespace std;
using ll = long long;
const int N = 2e5+1;
const ll INF = 1e12+1;

int n;
ll dp[N][2][2];
vector<pair<int,int> > g[N];

void dfs(int u, int par) {
	for(auto p: g[u]) if(p.first != par) dfs(p.first, u);
	vector<int> v, w, vals;
	for(auto p: g[u]) if(p.first != par) {
		v.push_back(p.first);
		w.push_back(p.second);
		vals.push_back(max(dp[p.first][1][0] + p.second, dp[p.first][0][0]));
	}
	//init
	dp[u][0][1] = dp[u][1][0] = dp[u][1][1] = -INF;

	// 00
	for(int i = 0; i < v.size(); i++) dp[u][0][0] += vals[i];

	//01
	ll mx = -INF;
	for(int i = 0; i < v.size(); i++) mx = max(max(dp[v[i]][0][1], dp[v[i]][1][1] + w[i]) - vals[i], mx);
	dp[u][0][1] = dp[u][0][0] + mx;
	mx = -INF;
	for(int i = 0; i < v.size(); i++) {
		dp[u][0][1] = max(dp[u][0][0] + dp[v[i]][0][0] + w[i] - vals[i] + mx, dp[u][0][1]);
		mx = max(max(dp[v[i]][0][0], dp[v[i]][0][1]) + w[i] - vals[i], mx);
	}
	mx = -INF;
	for(int i = v.size()-1; i >= 0; i--) {
		dp[u][0][1] = max(dp[u][0][0] + dp[v[i]][0][0] + w[i] - vals[i] + mx, dp[u][0][1]);
		mx = max(max(dp[v[i]][0][0], dp[v[i]][0][1]) + w[i] - vals[i], mx);
	}

	//10
	mx = -INF;
	for(int i = 0; i < v.size(); i++) mx = max(dp[v[i]][0][0] + w[i] - vals[i], mx);
	dp[u][1][0] = dp[u][0][0] + mx;

	//11
	mx = -INF;
	for(int i = 0; i < v.size(); i++) mx = max(dp[v[i]][0][1] + w[i] - vals[i], mx);
	dp[u][1][1] = dp[u][0][0] + mx;
	mx = -INF;
	for(int i = 0; i < v.size(); i++) {
		dp[u][1][1] = max(dp[u][0][0] + dp[v[i]][1][0] + w[i] - vals[i] + mx, dp[u][1][1]);
		mx = max(dp[v[i]][0][1] - vals[i], mx);
	}
	// cout << u << ' ' << dp[u][0][0] << ' ' << dp[u][0][1] << ' ' << dp[u][1][0] << ' ' << dp[u][1][1] << endl;
}

int main() {
	ios::sync_with_stdio(false);
	cin.tie(0);
	cin >> n;
	for(int i = 1, u, v, w; i < n; i++) {
		cin >> u >> v >> w;
		g[u].emplace_back(v, w);
		g[v].emplace_back(u, w);
	}
	dfs(1, 0);
	cout << max(dp[1][0][0], dp[1][0][1]);
}

Compilation message

beads.cpp: In function 'void dfs(int, int)':
beads.cpp:23:19: warning: comparison between signed and unsigned integer expressions [-Wsign-compare]
  for(int i = 0; i < v.size(); i++) dp[u][0][0] += vals[i];
                 ~~^~~~~~~~~~
beads.cpp:27:19: warning: comparison between signed and unsigned integer expressions [-Wsign-compare]
  for(int i = 0; i < v.size(); i++) mx = max(max(dp[v[i]][0][1], dp[v[i]][1][1] + w[i]) - vals[i], mx);
                 ~~^~~~~~~~~~
beads.cpp:30:19: warning: comparison between signed and unsigned integer expressions [-Wsign-compare]
  for(int i = 0; i < v.size(); i++) {
                 ~~^~~~~~~~~~
beads.cpp:42:19: warning: comparison between signed and unsigned integer expressions [-Wsign-compare]
  for(int i = 0; i < v.size(); i++) mx = max(dp[v[i]][0][0] + w[i] - vals[i], mx);
                 ~~^~~~~~~~~~
beads.cpp:47:19: warning: comparison between signed and unsigned integer expressions [-Wsign-compare]
  for(int i = 0; i < v.size(); i++) mx = max(dp[v[i]][0][1] + w[i] - vals[i], mx);
                 ~~^~~~~~~~~~
beads.cpp:50:19: warning: comparison between signed and unsigned integer expressions [-Wsign-compare]
  for(int i = 0; i < v.size(); i++) {
                 ~~^~~~~~~~~~

Subtask #1
13.0 / 13.0

# Verdict Execution time Memory Grader output
1 Correct 6 ms 4992 KB Output is correct
2 Correct 6 ms 5120 KB Output is correct
3 Correct 6 ms 5120 KB Output is correct
4 Correct 6 ms 5120 KB Output is correct
5 Correct 6 ms 5120 KB Output is correct
6 Correct 6 ms 5120 KB Output is correct
7 Correct 6 ms 4992 KB Output is correct
8 Correct 6 ms 5120 KB Output is correct
9 Correct 5 ms 4992 KB Output is correct
10 Correct 6 ms 5120 KB Output is correct
11 Correct 6 ms 5120 KB Output is correct
12 Correct 6 ms 5120 KB Output is correct

Subtask #2
15.0 / 15.0

# Verdict Execution time Memory Grader output
1 Correct 6 ms 4992 KB Output is correct
2 Correct 6 ms 5120 KB Output is correct
3 Correct 6 ms 5120 KB Output is correct
4 Correct 6 ms 5120 KB Output is correct
5 Correct 6 ms 5120 KB Output is correct
6 Correct 6 ms 5120 KB Output is correct
7 Correct 6 ms 4992 KB Output is correct
8 Correct 6 ms 5120 KB Output is correct
9 Correct 5 ms 4992 KB Output is correct
10 Correct 6 ms 5120 KB Output is correct
11 Correct 6 ms 5120 KB Output is correct
12 Correct 6 ms 5120 KB Output is correct
13 Correct 6 ms 5120 KB Output is correct
14 Correct 7 ms 5120 KB Output is correct
15 Correct 6 ms 5120 KB Output is correct
16 Correct 10 ms 5248 KB Output is correct
17 Correct 6 ms 5120 KB Output is correct
18 Correct 6 ms 4992 KB Output is correct
19 Correct 6 ms 4992 KB Output is correct
20 Correct 6 ms 4992 KB Output is correct
21 Correct 6 ms 5092 KB Output is correct
22 Correct 6 ms 4992 KB Output is correct

Subtask #3
29.0 / 29.0

# Verdict Execution time Memory Grader output
1 Correct 6 ms 4992 KB Output is correct
2 Correct 6 ms 5120 KB Output is correct
3 Correct 6 ms 5120 KB Output is correct
4 Correct 6 ms 5120 KB Output is correct
5 Correct 6 ms 5120 KB Output is correct
6 Correct 6 ms 5120 KB Output is correct
7 Correct 6 ms 4992 KB Output is correct
8 Correct 6 ms 5120 KB Output is correct
9 Correct 5 ms 4992 KB Output is correct
10 Correct 6 ms 5120 KB Output is correct
11 Correct 6 ms 5120 KB Output is correct
12 Correct 6 ms 5120 KB Output is correct
13 Correct 6 ms 5120 KB Output is correct
14 Correct 7 ms 5120 KB Output is correct
15 Correct 6 ms 5120 KB Output is correct
16 Correct 10 ms 5248 KB Output is correct
17 Correct 6 ms 5120 KB Output is correct
18 Correct 6 ms 4992 KB Output is correct
19 Correct 6 ms 4992 KB Output is correct
20 Correct 6 ms 4992 KB Output is correct
21 Correct 6 ms 5092 KB Output is correct
22 Correct 6 ms 4992 KB Output is correct
23 Correct 9 ms 5376 KB Output is correct
24 Correct 9 ms 5376 KB Output is correct
25 Correct 9 ms 5376 KB Output is correct
26 Correct 11 ms 5760 KB Output is correct
27 Correct 12 ms 5760 KB Output is correct
28 Correct 12 ms 6016 KB Output is correct
29 Correct 10 ms 5888 KB Output is correct
30 Correct 10 ms 5888 KB Output is correct
31 Correct 13 ms 6588 KB Output is correct

Subtask #4
43.0 / 43.0

# Verdict Execution time Memory Grader output
1 Correct 6 ms 4992 KB Output is correct
2 Correct 6 ms 5120 KB Output is correct
3 Correct 6 ms 5120 KB Output is correct
4 Correct 6 ms 5120 KB Output is correct
5 Correct 6 ms 5120 KB Output is correct
6 Correct 6 ms 5120 KB Output is correct
7 Correct 6 ms 4992 KB Output is correct
8 Correct 6 ms 5120 KB Output is correct
9 Correct 5 ms 4992 KB Output is correct
10 Correct 6 ms 5120 KB Output is correct
11 Correct 6 ms 5120 KB Output is correct
12 Correct 6 ms 5120 KB Output is correct
13 Correct 6 ms 5120 KB Output is correct
14 Correct 7 ms 5120 KB Output is correct
15 Correct 6 ms 5120 KB Output is correct
16 Correct 10 ms 5248 KB Output is correct
17 Correct 6 ms 5120 KB Output is correct
18 Correct 6 ms 4992 KB Output is correct
19 Correct 6 ms 4992 KB Output is correct
20 Correct 6 ms 4992 KB Output is correct
21 Correct 6 ms 5092 KB Output is correct
22 Correct 6 ms 4992 KB Output is correct
23 Correct 9 ms 5376 KB Output is correct
24 Correct 9 ms 5376 KB Output is correct
25 Correct 9 ms 5376 KB Output is correct
26 Correct 11 ms 5760 KB Output is correct
27 Correct 12 ms 5760 KB Output is correct
28 Correct 12 ms 6016 KB Output is correct
29 Correct 10 ms 5888 KB Output is correct
30 Correct 10 ms 5888 KB Output is correct
31 Correct 13 ms 6588 KB Output is correct
32 Correct 62 ms 8440 KB Output is correct
33 Correct 50 ms 8440 KB Output is correct
34 Correct 49 ms 8440 KB Output is correct
35 Correct 233 ms 18832 KB Output is correct
36 Correct 242 ms 18808 KB Output is correct
37 Correct 236 ms 18808 KB Output is correct
38 Correct 158 ms 22508 KB Output is correct
39 Correct 160 ms 21024 KB Output is correct
40 Correct 179 ms 20112 KB Output is correct
41 Correct 237 ms 29300 KB Output is correct