oj.uz

Submission #15859

# Submission time Handle Problem Language Result Execution time Memory
15859 2015-07-31T13:36:38 Z myungwoo Beads and wires (APIO14_beads) C++14
100 / 100
 441 ms 41100 KB 
#include <bits/stdc++.h>
using namespace std;

#define MAXN 200005
#define pb push_back
#define sz(v) ((int)(v).size())

int N;
int D[MAXN], E[MAXN];
int up[MAXN], par[MAXN], V[MAXN];
int ans;
vector <int> con[MAXN], conv[MAXN], tcon[MAXN];

void dp(int n, int from)
{
	vector <int> arr;
	for (int i=sz(con[n]);i--;){
		int t = con[n][i], v = conv[n][i];
		if (t == from) continue;
		up[t] = v; par[t] = n; dp(t, n);
		arr.pb(t);
	}
	D[n] = E[n] = 0;
	for (int t: arr){
		V[t] = max(D[t], E[t]);
		D[n] += V[t]; 
	}
	for (int t: arr) E[n] = max(E[n], D[n] - V[t] + D[t] + up[t] + up[n]);
	tcon[n] = arr;
}

void dfs(int n, int d, int e)
{
	int v = max(d, e), sum = D[n] + v;
	ans = max(ans, sum);
	int mx1 = -2e9, mx1t, mx2 = -2e9;
	if (par[n]) mx1 = -v + d + up[n], mx1t = 0;
	for (int t: tcon[n]){
		int val = -V[t] + D[t] + up[t];
		if (mx1 <= val)
			mx2 = mx1, mx1 = val, mx1t = t;
		else if (mx2 < val)
			mx2 = val;
	}
	for (int t: tcon[n]){
		int nxt_d = sum - max(D[t], E[t]);
		dfs(t, nxt_d, mx1t == t ? nxt_d + mx2 + up[t] : nxt_d + mx1 + up[t]);
	}
}

int main()
{
	scanf("%d", &N);
	for (int i=1;i<N;i++){
		int a, b, c;
		scanf("%d%d%d", &a, &b, &c);
		con[a].pb(b); conv[a].pb(c);
		con[b].pb(a); conv[b].pb(c);
	}
	dp(1, 0);
	dfs(1, 0, 0);
	printf("%d\n", ans);
}

Compilation message

beads.cpp: In function 'int main()':
beads.cpp:53:7: warning: ignoring return value of 'int scanf(const char*, ...)', declared with attribute warn_unused_result [-Wunused-result]
  scanf("%d", &N);
  ~~~~~^~~~~~~~~~
beads.cpp:56:8: warning: ignoring return value of 'int scanf(const char*, ...)', declared with attribute warn_unused_result [-Wunused-result]
   scanf("%d%d%d", &a, &b, &c);
   ~~~~~^~~~~~~~~~~~~~~~~~~~~~

Subtask #1
13.0 / 13.0

# Verdict Execution time Memory Grader output
1 Correct 13 ms 14464 KB Output is correct
2 Correct 14 ms 14464 KB Output is correct
3 Correct 14 ms 14464 KB Output is correct
4 Correct 13 ms 14464 KB Output is correct
5 Correct 14 ms 14464 KB Output is correct
6 Correct 14 ms 14464 KB Output is correct
7 Correct 13 ms 14464 KB Output is correct
8 Correct 14 ms 14464 KB Output is correct
9 Correct 13 ms 14464 KB Output is correct
10 Correct 13 ms 14464 KB Output is correct
11 Correct 13 ms 14492 KB Output is correct
12 Correct 14 ms 14436 KB Output is correct

Subtask #2
15.0 / 15.0

# Verdict Execution time Memory Grader output
1 Correct 13 ms 14464 KB Output is correct
2 Correct 14 ms 14464 KB Output is correct
3 Correct 14 ms 14464 KB Output is correct
4 Correct 13 ms 14464 KB Output is correct
5 Correct 14 ms 14464 KB Output is correct
6 Correct 14 ms 14464 KB Output is correct
7 Correct 13 ms 14464 KB Output is correct
8 Correct 14 ms 14464 KB Output is correct
9 Correct 13 ms 14464 KB Output is correct
10 Correct 13 ms 14464 KB Output is correct
11 Correct 13 ms 14492 KB Output is correct
12 Correct 14 ms 14436 KB Output is correct
13 Correct 14 ms 14464 KB Output is correct
14 Correct 13 ms 14424 KB Output is correct
15 Correct 13 ms 14464 KB Output is correct
16 Correct 14 ms 14436 KB Output is correct
17 Correct 13 ms 14464 KB Output is correct
18 Correct 14 ms 14464 KB Output is correct
19 Correct 15 ms 14464 KB Output is correct
20 Correct 14 ms 14504 KB Output is correct
21 Correct 14 ms 14464 KB Output is correct
22 Correct 13 ms 14464 KB Output is correct

Subtask #3
29.0 / 29.0

# Verdict Execution time Memory Grader output
1 Correct 13 ms 14464 KB Output is correct
2 Correct 14 ms 14464 KB Output is correct
3 Correct 14 ms 14464 KB Output is correct
4 Correct 13 ms 14464 KB Output is correct
5 Correct 14 ms 14464 KB Output is correct
6 Correct 14 ms 14464 KB Output is correct
7 Correct 13 ms 14464 KB Output is correct
8 Correct 14 ms 14464 KB Output is correct
9 Correct 13 ms 14464 KB Output is correct
10 Correct 13 ms 14464 KB Output is correct
11 Correct 13 ms 14492 KB Output is correct
12 Correct 14 ms 14436 KB Output is correct
13 Correct 14 ms 14464 KB Output is correct
14 Correct 13 ms 14424 KB Output is correct
15 Correct 13 ms 14464 KB Output is correct
16 Correct 14 ms 14436 KB Output is correct
17 Correct 13 ms 14464 KB Output is correct
18 Correct 14 ms 14464 KB Output is correct
19 Correct 15 ms 14464 KB Output is correct
20 Correct 14 ms 14504 KB Output is correct
21 Correct 14 ms 14464 KB Output is correct
22 Correct 13 ms 14464 KB Output is correct
23 Correct 17 ms 14976 KB Output is correct
24 Correct 18 ms 14968 KB Output is correct
25 Correct 18 ms 14976 KB Output is correct
26 Correct 23 ms 15488 KB Output is correct
27 Correct 22 ms 15488 KB Output is correct
28 Correct 20 ms 15488 KB Output is correct
29 Correct 20 ms 15360 KB Output is correct
30 Correct 20 ms 15480 KB Output is correct
31 Correct 22 ms 16000 KB Output is correct

Subtask #4
43.0 / 43.0

# Verdict Execution time Memory Grader output
1 Correct 13 ms 14464 KB Output is correct
2 Correct 14 ms 14464 KB Output is correct
3 Correct 14 ms 14464 KB Output is correct
4 Correct 13 ms 14464 KB Output is correct
5 Correct 14 ms 14464 KB Output is correct
6 Correct 14 ms 14464 KB Output is correct
7 Correct 13 ms 14464 KB Output is correct
8 Correct 14 ms 14464 KB Output is correct
9 Correct 13 ms 14464 KB Output is correct
10 Correct 13 ms 14464 KB Output is correct
11 Correct 13 ms 14492 KB Output is correct
12 Correct 14 ms 14436 KB Output is correct
13 Correct 14 ms 14464 KB Output is correct
14 Correct 13 ms 14424 KB Output is correct
15 Correct 13 ms 14464 KB Output is correct
16 Correct 14 ms 14436 KB Output is correct
17 Correct 13 ms 14464 KB Output is correct
18 Correct 14 ms 14464 KB Output is correct
19 Correct 15 ms 14464 KB Output is correct
20 Correct 14 ms 14504 KB Output is correct
21 Correct 14 ms 14464 KB Output is correct
22 Correct 13 ms 14464 KB Output is correct
23 Correct 17 ms 14976 KB Output is correct
24 Correct 18 ms 14968 KB Output is correct
25 Correct 18 ms 14976 KB Output is correct
26 Correct 23 ms 15488 KB Output is correct
27 Correct 22 ms 15488 KB Output is correct
28 Correct 20 ms 15488 KB Output is correct
29 Correct 20 ms 15360 KB Output is correct
30 Correct 20 ms 15480 KB Output is correct
31 Correct 22 ms 16000 KB Output is correct
32 Correct 81 ms 19476 KB Output is correct
33 Correct 80 ms 19496 KB Output is correct
34 Correct 70 ms 19448 KB Output is correct
35 Correct 420 ms 34544 KB Output is correct
36 Correct 414 ms 34528 KB Output is correct
37 Correct 441 ms 34600 KB Output is correct
38 Correct 291 ms 34012 KB Output is correct
39 Correct 308 ms 33812 KB Output is correct
40 Correct 309 ms 33928 KB Output is correct
41 Correct 401 ms 41100 KB Output is correct