oj.uz

Submission #198675

# Submission time Handle Problem Language Result Execution time Memory
198675 2020-01-27T09:09:12 Z gs18081 Beads and wires (APIO14_beads) C++11
100 / 100
 285 ms 32236 KB 
#include <bits/stdc++.h>

using namespace std;

typedef pair<int,int> pi;
typedef long long int ll;
	
const int MAXN = 202020;
const ll MAX = 2e9;

vector<pi> edge[MAXN];
ll plen[MAXN];
ll dp1[MAXN];
ll dp2[MAXN];
ll dp3[MAXN];
ll dp4[MAXN];
int N;

void dfs(int node,int par){
	ll mx2 = -MAX;
	ll mx4 = -MAX;
	vector<pi> vect3;
	int ccnt = 0;
	for(auto i : edge[node]){
		if(i.first == par) continue;
		ccnt++;
		plen[i.first] = i.second;
		dfs(i.first,node);
		dp1[node] += max(dp1[i.first] , dp2[i.first]);
		mx2 = max(mx2 , dp1[i.first] + plen[i.first] - max(dp1[i.first],dp2[i.first])); 
		mx4 = max(mx4 , dp3[i.first] + plen[i.first] - max(dp1[i.first],dp2[i.first])); 
		vect3.push_back(pi(dp1[i.first] + plen[i.first] - max(dp1[i.first],dp2[i.first]), i.first));
	}
	sort(vect3.begin(),vect3.end(),greater<pi>());
	dp2[node] = dp1[node] + mx2 + plen[node];
	dp4[node] = dp1[node] + mx4 + plen[node];
	dp3[node] = dp1[node];
	if(ccnt > 1){
		for(auto i : edge[node]){
			if(i.first == par) continue;
			int j;
			for(j = 0;j<vect3.size();j++){
				if(i.first != vect3[j].second) break;
			}
			if(j == vect3.size()) continue;
			dp3[node] = max(dp3[node] , dp1[node] + dp3[i.first] + plen[i.first] - max(dp1[i.first] , dp2[i.first]) + vect3[j].first);
		}
	}
	for(auto i : edge[node]){
		if(i.first == par) continue;
		dp3[node] = max(dp3[node] , dp1[node] + dp3[i.first] - max(dp1[i.first] , dp2[i.first]));
		dp3[node] = max(dp3[node] , dp1[node] + dp4[i.first] - max(dp1[i.first] , dp2[i.first]));
	}
	assert(dp4[node] >= dp2[node]);
//	printf("%d %lld %lld %lld %lld\n",node,dp1[node],dp2[node],dp3[node],dp4[node]);


	

}



int main(){
	scanf("%d",&N);
	for(int i=1;i<N;i++){
		int a,b,c;
		scanf("%d %d %d",&a,&b,&c);
		edge[a].push_back(pi(b,c));
		edge[b].push_back(pi(a,c));
	}
	dfs(1,1);
	printf("%lld\n",max(dp1[1],dp3[1]));
	return 0;
}

Compilation message

beads.cpp: In function 'void dfs(int, int)':
beads.cpp:42:15: warning: comparison between signed and unsigned integer expressions [-Wsign-compare]
    for(j = 0;j<vect3.size();j++){
              ~^~~~~~~~~~~~~
beads.cpp:45:9: warning: comparison between signed and unsigned integer expressions [-Wsign-compare]
    if(j == vect3.size()) continue;
       ~~^~~~~~~~~~~~~~~
beads.cpp: In function 'int main()':
beads.cpp:65:7: warning: ignoring return value of 'int scanf(const char*, ...)', declared with attribute warn_unused_result [-Wunused-result]
  scanf("%d",&N);
  ~~~~~^~~~~~~~~
beads.cpp:68:8: 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 8 ms 5112 KB Output is correct
2 Correct 8 ms 5112 KB Output is correct
3 Correct 8 ms 5112 KB Output is correct
4 Correct 8 ms 5112 KB Output is correct
5 Correct 8 ms 5112 KB Output is correct
6 Correct 8 ms 5112 KB Output is correct
7 Correct 8 ms 5112 KB Output is correct
8 Correct 8 ms 5112 KB Output is correct
9 Correct 8 ms 5112 KB Output is correct
10 Correct 8 ms 5112 KB Output is correct
11 Correct 8 ms 5112 KB Output is correct
12 Correct 8 ms 5116 KB Output is correct

Subtask #2
15.0 / 15.0

# Verdict Execution time Memory Grader output
1 Correct 8 ms 5112 KB Output is correct
2 Correct 8 ms 5112 KB Output is correct
3 Correct 8 ms 5112 KB Output is correct
4 Correct 8 ms 5112 KB Output is correct
5 Correct 8 ms 5112 KB Output is correct
6 Correct 8 ms 5112 KB Output is correct
7 Correct 8 ms 5112 KB Output is correct
8 Correct 8 ms 5112 KB Output is correct
9 Correct 8 ms 5112 KB Output is correct
10 Correct 8 ms 5112 KB Output is correct
11 Correct 8 ms 5112 KB Output is correct
12 Correct 8 ms 5116 KB Output is correct
13 Correct 9 ms 5112 KB Output is correct
14 Correct 8 ms 5116 KB Output is correct
15 Correct 8 ms 5112 KB Output is correct
16 Correct 8 ms 5112 KB Output is correct
17 Correct 9 ms 5112 KB Output is correct
18 Correct 8 ms 5112 KB Output is correct
19 Correct 9 ms 5112 KB Output is correct
20 Correct 9 ms 5112 KB Output is correct
21 Correct 9 ms 5112 KB Output is correct
22 Correct 9 ms 5116 KB Output is correct

Subtask #3
29.0 / 29.0

# Verdict Execution time Memory Grader output
1 Correct 8 ms 5112 KB Output is correct
2 Correct 8 ms 5112 KB Output is correct
3 Correct 8 ms 5112 KB Output is correct
4 Correct 8 ms 5112 KB Output is correct
5 Correct 8 ms 5112 KB Output is correct
6 Correct 8 ms 5112 KB Output is correct
7 Correct 8 ms 5112 KB Output is correct
8 Correct 8 ms 5112 KB Output is correct
9 Correct 8 ms 5112 KB Output is correct
10 Correct 8 ms 5112 KB Output is correct
11 Correct 8 ms 5112 KB Output is correct
12 Correct 8 ms 5116 KB Output is correct
13 Correct 9 ms 5112 KB Output is correct
14 Correct 8 ms 5116 KB Output is correct
15 Correct 8 ms 5112 KB Output is correct
16 Correct 8 ms 5112 KB Output is correct
17 Correct 9 ms 5112 KB Output is correct
18 Correct 8 ms 5112 KB Output is correct
19 Correct 9 ms 5112 KB Output is correct
20 Correct 9 ms 5112 KB Output is correct
21 Correct 9 ms 5112 KB Output is correct
22 Correct 9 ms 5116 KB Output is correct
23 Correct 12 ms 5628 KB Output is correct
24 Correct 12 ms 5496 KB Output is correct
25 Correct 12 ms 5624 KB Output is correct
26 Correct 15 ms 6008 KB Output is correct
27 Correct 16 ms 6008 KB Output is correct
28 Correct 15 ms 6264 KB Output is correct
29 Correct 15 ms 6008 KB Output is correct
30 Correct 17 ms 6136 KB Output is correct
31 Correct 15 ms 6648 KB Output is correct

Subtask #4
43.0 / 43.0

# Verdict Execution time Memory Grader output
1 Correct 8 ms 5112 KB Output is correct
2 Correct 8 ms 5112 KB Output is correct
3 Correct 8 ms 5112 KB Output is correct
4 Correct 8 ms 5112 KB Output is correct
5 Correct 8 ms 5112 KB Output is correct
6 Correct 8 ms 5112 KB Output is correct
7 Correct 8 ms 5112 KB Output is correct
8 Correct 8 ms 5112 KB Output is correct
9 Correct 8 ms 5112 KB Output is correct
10 Correct 8 ms 5112 KB Output is correct
11 Correct 8 ms 5112 KB Output is correct
12 Correct 8 ms 5116 KB Output is correct
13 Correct 9 ms 5112 KB Output is correct
14 Correct 8 ms 5116 KB Output is correct
15 Correct 8 ms 5112 KB Output is correct
16 Correct 8 ms 5112 KB Output is correct
17 Correct 9 ms 5112 KB Output is correct
18 Correct 8 ms 5112 KB Output is correct
19 Correct 9 ms 5112 KB Output is correct
20 Correct 9 ms 5112 KB Output is correct
21 Correct 9 ms 5112 KB Output is correct
22 Correct 9 ms 5116 KB Output is correct
23 Correct 12 ms 5628 KB Output is correct
24 Correct 12 ms 5496 KB Output is correct
25 Correct 12 ms 5624 KB Output is correct
26 Correct 15 ms 6008 KB Output is correct
27 Correct 16 ms 6008 KB Output is correct
28 Correct 15 ms 6264 KB Output is correct
29 Correct 15 ms 6008 KB Output is correct
30 Correct 17 ms 6136 KB Output is correct
31 Correct 15 ms 6648 KB Output is correct
32 Correct 57 ms 9720 KB Output is correct
33 Correct 54 ms 9720 KB Output is correct
34 Correct 53 ms 9720 KB Output is correct
35 Correct 279 ms 23928 KB Output is correct
36 Correct 281 ms 23928 KB Output is correct
37 Correct 285 ms 23928 KB Output is correct
38 Correct 211 ms 27444 KB Output is correct
39 Correct 221 ms 24792 KB Output is correct
40 Correct 220 ms 25568 KB Output is correct
41 Correct 279 ms 32236 KB Output is correct