oj.uz

Submission #265500

# Submission time Handle Problem Language Result Execution time Memory
265500 2020-08-14T22:26:48 Z square1001 Beads and wires (APIO14_beads) C++14
28 / 100
 1000 ms 640 KB 
#include <vector>
#include <iostream>
#include <algorithm>
#include <functional>
using namespace std;
const int inf = 2012345678;
int main() {
	// step #1. read input
	cin.tie(0);
	ios_base::sync_with_stdio(false);
	int N;
	cin >> N;
	vector<int> ga(N - 1), gb(N - 1), gw(N - 1);
	for(int i = 0; i < N - 1; ++i) {
		cin >> ga[i] >> gb[i] >> gw[i];
		--ga[i], --gb[i];
	}
	// step #2. construct a graph
	vector<int> sep(N + 1);
	for(int i = 0; i < N - 1; ++i) {
		++sep[ga[i] + 1];
		++sep[gb[i] + 1];
	}
	for(int i = 0; i < N; ++i) {
		sep[i + 1] += sep[i];
	}
	vector<int> ctr(sep);
	vector<int> to(2 * N - 2), cost(2 * N - 2);
	for(int i = 0; i < N - 1; ++i) {
		to[ctr[ga[i]]] = gb[i]; cost[ctr[ga[i]]++] = gw[i];
		to[ctr[gb[i]]] = ga[i]; cost[ctr[gb[i]]++] = gw[i];
	}
	// step #3. calculation
	function<pair<int, int>(int, int)> solve = [&](int pos, int pre) {
		// returns = (no mid-blue, one mid-blue)
		int sumcost = 0, delta = -inf;
		for(int i = sep[pos]; i < sep[pos + 1]; ++i) {
			if(to[i] == pre) continue;
			pair<int, int> res = solve(to[i], pos);
			sumcost += max(res.first, res.second + cost[i]);
			delta = max(delta, cost[i] - max(res.second + cost[i] - res.first, 0));
		}
		return make_pair(sumcost, sumcost + delta);
	};
	int ans = 0;
	for(int i = 0; i < N; ++i) {
		pair<int, int> res = solve(i, -1);
		ans = max(ans, res.first);
	}
	// step #4. print the answer
	cout << ans << endl;
	return 0;
}

Subtask #1
13.0 / 13.0

# Verdict Execution time Memory Grader output
1 Correct 0 ms 384 KB Output is correct
2 Correct 0 ms 384 KB Output is correct
3 Correct 0 ms 384 KB Output is correct
4 Correct 0 ms 384 KB Output is correct
5 Correct 0 ms 384 KB Output is correct
6 Correct 0 ms 384 KB Output is correct
7 Correct 0 ms 384 KB Output is correct
8 Correct 0 ms 384 KB Output is correct
9 Correct 1 ms 384 KB Output is correct
10 Correct 0 ms 384 KB Output is correct
11 Correct 1 ms 384 KB Output is correct
12 Correct 0 ms 384 KB Output is correct

Subtask #2
15.0 / 15.0

# Verdict Execution time Memory Grader output
1 Correct 0 ms 384 KB Output is correct
2 Correct 0 ms 384 KB Output is correct
3 Correct 0 ms 384 KB Output is correct
4 Correct 0 ms 384 KB Output is correct
5 Correct 0 ms 384 KB Output is correct
6 Correct 0 ms 384 KB Output is correct
7 Correct 0 ms 384 KB Output is correct
8 Correct 0 ms 384 KB Output is correct
9 Correct 1 ms 384 KB Output is correct
10 Correct 0 ms 384 KB Output is correct
11 Correct 1 ms 384 KB Output is correct
12 Correct 0 ms 384 KB Output is correct
13 Correct 1 ms 384 KB Output is correct
14 Correct 1 ms 384 KB Output is correct
15 Correct 1 ms 384 KB Output is correct
16 Correct 1 ms 384 KB Output is correct
17 Correct 1 ms 384 KB Output is correct
18 Correct 1 ms 384 KB Output is correct
19 Correct 2 ms 384 KB Output is correct
20 Correct 1 ms 384 KB Output is correct
21 Correct 1 ms 384 KB Output is correct
22 Correct 1 ms 384 KB Output is correct

Subtask #3
0 / 29.0

# Verdict Execution time Memory Grader output
1 Correct 0 ms 384 KB Output is correct
2 Correct 0 ms 384 KB Output is correct
3 Correct 0 ms 384 KB Output is correct
4 Correct 0 ms 384 KB Output is correct
5 Correct 0 ms 384 KB Output is correct
6 Correct 0 ms 384 KB Output is correct
7 Correct 0 ms 384 KB Output is correct
8 Correct 0 ms 384 KB Output is correct
9 Correct 1 ms 384 KB Output is correct
10 Correct 0 ms 384 KB Output is correct
11 Correct 1 ms 384 KB Output is correct
12 Correct 0 ms 384 KB Output is correct
13 Correct 1 ms 384 KB Output is correct
14 Correct 1 ms 384 KB Output is correct
15 Correct 1 ms 384 KB Output is correct
16 Correct 1 ms 384 KB Output is correct
17 Correct 1 ms 384 KB Output is correct
18 Correct 1 ms 384 KB Output is correct
19 Correct 2 ms 384 KB Output is correct
20 Correct 1 ms 384 KB Output is correct
21 Correct 1 ms 384 KB Output is correct
22 Correct 1 ms 384 KB Output is correct
23 Correct 741 ms 560 KB Output is correct
24 Correct 703 ms 632 KB Output is correct
25 Correct 691 ms 512 KB Output is correct
26 Execution timed out 1088 ms 640 KB Time limit exceeded
27 Halted 0 ms 0 KB -

Subtask #4
0 / 43.0

# Verdict Execution time Memory Grader output
1 Correct 0 ms 384 KB Output is correct
2 Correct 0 ms 384 KB Output is correct
3 Correct 0 ms 384 KB Output is correct
4 Correct 0 ms 384 KB Output is correct
5 Correct 0 ms 384 KB Output is correct
6 Correct 0 ms 384 KB Output is correct
7 Correct 0 ms 384 KB Output is correct
8 Correct 0 ms 384 KB Output is correct
9 Correct 1 ms 384 KB Output is correct
10 Correct 0 ms 384 KB Output is correct
11 Correct 1 ms 384 KB Output is correct
12 Correct 0 ms 384 KB Output is correct
13 Correct 1 ms 384 KB Output is correct
14 Correct 1 ms 384 KB Output is correct
15 Correct 1 ms 384 KB Output is correct
16 Correct 1 ms 384 KB Output is correct
17 Correct 1 ms 384 KB Output is correct
18 Correct 1 ms 384 KB Output is correct
19 Correct 2 ms 384 KB Output is correct
20 Correct 1 ms 384 KB Output is correct
21 Correct 1 ms 384 KB Output is correct
22 Correct 1 ms 384 KB Output is correct
23 Correct 741 ms 560 KB Output is correct
24 Correct 703 ms 632 KB Output is correct
25 Correct 691 ms 512 KB Output is correct
26 Execution timed out 1088 ms 640 KB Time limit exceeded
27 Halted 0 ms 0 KB -