Submission #124798

# Submission time Handle Problem Language Result Execution time Memory
124798 2019-07-04T02:08:46 Z model_code Cat in a tree (BOI17_catinatree) C++17
100 / 100
123 ms 20008 KB
#include<cstdio>
#include<iostream>
#include<vector>
#include<algorithm>

using namespace std;

int N,D;
vector<vector<int> > T;
vector<int> opt, optdist, sacrdist;

void DFS(int pos) {
	// Base case: pos is a leaf
	if(T[pos].size() == 0) {
		opt[pos] = 1;
		optdist[pos] = 0;
		sacrdist[pos] = D;
		return;
	}
	
	int v = T[pos][0];
	DFS(v);
	if(optdist[v] + 1 >= D) {
		opt[pos] = opt[v] + 1;
		optdist[pos] = 0;
		sacrdist[pos] = optdist[v] + 1;
	} else {
		opt[pos] = opt[v];
		optdist[pos] = optdist[v] + 1;
		sacrdist[pos] = sacrdist[v] + 1;
	}
	
	for(int i = 1; i < T[pos].size(); ++i) {
		int v = T[pos][i];
		DFS(v);
		
		// distance between closest points and 
		// distance to root
		// in the 4 possible solution combinations. 
		int doo = optdist[pos] + optdist[v] + 1;
		int mdoo = min(optdist[pos], optdist[v] + 1);
		
		int dos = optdist[pos] + sacrdist[v] + 1;
		int mdos = min(optdist[pos], sacrdist[v] + 1);

		int dso = sacrdist[pos] + optdist[v] + 1;
		int mdso = min(sacrdist[pos], optdist[v] + 1);

		int dss = sacrdist[pos] + sacrdist[v] + 1;
		int mdss = min(sacrdist[pos], sacrdist[v] + 1);
		
		if(doo >= D) {
			opt[pos] += opt[v];
			optdist[pos] = mdoo;
			sacrdist[pos] = max(mdos, mdso);
		} else {
			opt[pos] += opt[v] - 1;
			if(dos >= D) optdist[pos] = mdos; else optdist[pos] = 0;
			if(dso >= D) optdist[pos] = max(optdist[pos], mdso);
			sacrdist[pos] = mdss;
		} 
	}
}

int main() {
	scanf("%d%d", &N, &D);
	T = vector<vector<int> > (N);
	opt = vector<int> (N, 0);
	optdist = vector<int> (N, 0);
	sacrdist = vector<int> (N, 0);
	for(int i = 1; i < N; ++i) {
		int a;
		scanf("%d", &a);
		T[a].push_back(i);
	}
	DFS(0);
	printf("%d\n", opt[0]);
	return 0;
}

Compilation message

catinatree.cpp: In function 'void DFS(int)':
catinatree.cpp:33:19: warning: comparison between signed and unsigned integer expressions [-Wsign-compare]
  for(int i = 1; i < T[pos].size(); ++i) {
                 ~~^~~~~~~~~~~~~~~
catinatree.cpp:49:7: warning: unused variable 'dss' [-Wunused-variable]
   int dss = sacrdist[pos] + sacrdist[v] + 1;
       ^~~
catinatree.cpp: In function 'int main()':
catinatree.cpp:66:7: warning: ignoring return value of 'int scanf(const char*, ...)', declared with attribute warn_unused_result [-Wunused-result]
  scanf("%d%d", &N, &D);
  ~~~~~^~~~~~~~~~~~~~~~
catinatree.cpp:73:8: warning: ignoring return value of 'int scanf(const char*, ...)', declared with attribute warn_unused_result [-Wunused-result]
   scanf("%d", &a);
   ~~~~~^~~~~~~~~~
# Verdict Execution time Memory Grader output
1 Correct 2 ms 424 KB Output is correct
2 Correct 2 ms 376 KB Output is correct
3 Correct 2 ms 376 KB Output is correct
4 Correct 2 ms 376 KB Output is correct
5 Correct 2 ms 256 KB Output is correct
6 Correct 2 ms 256 KB Output is correct
7 Correct 2 ms 256 KB Output is correct
8 Correct 2 ms 256 KB Output is correct
9 Correct 2 ms 256 KB Output is correct
10 Correct 2 ms 256 KB Output is correct
11 Correct 2 ms 376 KB Output is correct
12 Correct 2 ms 256 KB Output is correct
13 Correct 2 ms 256 KB Output is correct
14 Correct 2 ms 376 KB Output is correct
15 Correct 2 ms 256 KB Output is correct
16 Correct 2 ms 256 KB Output is correct
17 Correct 2 ms 256 KB Output is correct
18 Correct 2 ms 376 KB Output is correct
19 Correct 2 ms 256 KB Output is correct
20 Correct 2 ms 256 KB Output is correct
# Verdict Execution time Memory Grader output
1 Correct 2 ms 424 KB Output is correct
2 Correct 2 ms 376 KB Output is correct
3 Correct 2 ms 376 KB Output is correct
4 Correct 2 ms 376 KB Output is correct
5 Correct 2 ms 256 KB Output is correct
6 Correct 2 ms 256 KB Output is correct
7 Correct 2 ms 256 KB Output is correct
8 Correct 2 ms 256 KB Output is correct
9 Correct 2 ms 256 KB Output is correct
10 Correct 2 ms 256 KB Output is correct
11 Correct 2 ms 376 KB Output is correct
12 Correct 2 ms 256 KB Output is correct
13 Correct 2 ms 256 KB Output is correct
14 Correct 2 ms 376 KB Output is correct
15 Correct 2 ms 256 KB Output is correct
16 Correct 2 ms 256 KB Output is correct
17 Correct 2 ms 256 KB Output is correct
18 Correct 2 ms 376 KB Output is correct
19 Correct 2 ms 256 KB Output is correct
20 Correct 2 ms 256 KB Output is correct
21 Correct 2 ms 508 KB Output is correct
22 Correct 2 ms 376 KB Output is correct
23 Correct 2 ms 376 KB Output is correct
24 Correct 2 ms 380 KB Output is correct
25 Correct 3 ms 376 KB Output is correct
26 Correct 3 ms 376 KB Output is correct
27 Correct 2 ms 376 KB Output is correct
28 Correct 2 ms 376 KB Output is correct
29 Correct 3 ms 376 KB Output is correct
30 Correct 2 ms 376 KB Output is correct
31 Correct 2 ms 376 KB Output is correct
32 Correct 2 ms 376 KB Output is correct
33 Correct 2 ms 376 KB Output is correct
34 Correct 2 ms 376 KB Output is correct
35 Correct 2 ms 376 KB Output is correct
36 Correct 2 ms 380 KB Output is correct
37 Correct 2 ms 376 KB Output is correct
38 Correct 2 ms 376 KB Output is correct
39 Correct 3 ms 504 KB Output is correct
40 Correct 2 ms 504 KB Output is correct
# Verdict Execution time Memory Grader output
1 Correct 2 ms 424 KB Output is correct
2 Correct 2 ms 376 KB Output is correct
3 Correct 2 ms 376 KB Output is correct
4 Correct 2 ms 376 KB Output is correct
5 Correct 2 ms 256 KB Output is correct
6 Correct 2 ms 256 KB Output is correct
7 Correct 2 ms 256 KB Output is correct
8 Correct 2 ms 256 KB Output is correct
9 Correct 2 ms 256 KB Output is correct
10 Correct 2 ms 256 KB Output is correct
11 Correct 2 ms 376 KB Output is correct
12 Correct 2 ms 256 KB Output is correct
13 Correct 2 ms 256 KB Output is correct
14 Correct 2 ms 376 KB Output is correct
15 Correct 2 ms 256 KB Output is correct
16 Correct 2 ms 256 KB Output is correct
17 Correct 2 ms 256 KB Output is correct
18 Correct 2 ms 376 KB Output is correct
19 Correct 2 ms 256 KB Output is correct
20 Correct 2 ms 256 KB Output is correct
21 Correct 2 ms 508 KB Output is correct
22 Correct 2 ms 376 KB Output is correct
23 Correct 2 ms 376 KB Output is correct
24 Correct 2 ms 380 KB Output is correct
25 Correct 3 ms 376 KB Output is correct
26 Correct 3 ms 376 KB Output is correct
27 Correct 2 ms 376 KB Output is correct
28 Correct 2 ms 376 KB Output is correct
29 Correct 3 ms 376 KB Output is correct
30 Correct 2 ms 376 KB Output is correct
31 Correct 2 ms 376 KB Output is correct
32 Correct 2 ms 376 KB Output is correct
33 Correct 2 ms 376 KB Output is correct
34 Correct 2 ms 376 KB Output is correct
35 Correct 2 ms 376 KB Output is correct
36 Correct 2 ms 380 KB Output is correct
37 Correct 2 ms 376 KB Output is correct
38 Correct 2 ms 376 KB Output is correct
39 Correct 3 ms 504 KB Output is correct
40 Correct 2 ms 504 KB Output is correct
41 Correct 57 ms 10772 KB Output is correct
42 Correct 43 ms 5528 KB Output is correct
43 Correct 39 ms 5496 KB Output is correct
44 Correct 39 ms 5556 KB Output is correct
45 Correct 37 ms 5496 KB Output is correct
46 Correct 93 ms 10616 KB Output is correct
47 Correct 99 ms 10672 KB Output is correct
48 Correct 123 ms 10556 KB Output is correct
49 Correct 116 ms 10692 KB Output is correct
50 Correct 22 ms 4344 KB Output is correct
51 Correct 23 ms 4472 KB Output is correct
52 Correct 23 ms 4344 KB Output is correct
53 Correct 46 ms 8568 KB Output is correct
54 Correct 47 ms 8440 KB Output is correct
55 Correct 46 ms 8440 KB Output is correct
56 Correct 3 ms 504 KB Output is correct
57 Correct 9 ms 3576 KB Output is correct
58 Correct 37 ms 15084 KB Output is correct
59 Correct 83 ms 20008 KB Output is correct
60 Correct 62 ms 11512 KB Output is correct
61 Correct 67 ms 11000 KB Output is correct