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IDProblemSubmitterResultTimeMemoryLanguageFile sizeSubmit timeJudge time
#780217#2596. Even ForestniumachaorenWA 213ms96752kbC++14852b2024-11-25 08:49:322024-11-25 08:49:32

Judging History

你现在查看的是最新测评结果

  • [2024-11-25 08:49:32]
  • 评测
  • 测评结果:WA
  • 用时:213ms
  • 内存:96752kb
  • [2024-11-25 08:49:32]
  • 提交

answer

#include<bits/stdc++.h>
inline void read(int &x){
	x=0;char ch=getchar();
	while(!isdigit(ch))ch=getchar();
	while(isdigit(ch)){
		x=(x<<1)+(x<<3)+(ch^48);
		ch=getchar();
	}
}
using namespace std;
const int maxn=1e6+10;
int n,rt,dep[maxn],dp[maxn][2];
vector<int>e[maxn<<1];
void dfs(int u,int fa){
	dep[u]=dep[fa]+1;
	int siz=0;
	for(int v:e[u]){
		if(v==fa)continue;
		siz++;
		dfs(v,u);
		dp[u][0]+=min(dp[v][0],dp[v][1]+1);
		dp[u][1]+=min(dp[v][1],dp[v][0]+1);
	}
	if(!siz){
		dp[u][dep[u]&1]=1;
	}
}
int main(){
	read(n);
	for(int i=1;i<n;i++){
		int u,v;
		read(u),read(v);
		e[u].push_back(v),e[v].push_back(u);
	}
	int cnt=0;
	for(int i=1;i<=n;i++){
		if(e[i].size()==1)cnt++;
	}
	if(cnt==2){
		cout<<((n&1)^1)<<'\n';
		return 0;
	}
	rt=1;
	dfs(1,0);
	cout<<min(dp[1][0],dp[1][1]);
	return 0;
}

Details

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Test #1:

score: 100
Accepted
time: 8ms
memory: 51908kb

input:

4
1 2
2 3
3 4

output:

1

result:

ok 1 number(s): "1"

Test #2:

score: 0
Accepted
time: 6ms
memory: 50500kb

input:

4
1 2
1 3
1 4

output:

0

result:

ok 1 number(s): "0"

Test #3:

score: 0
Accepted
time: 8ms
memory: 50496kb

input:

6
1 2
2 3
4 2
4 5
6 4

output:

1

result:

ok 1 number(s): "1"

Test #4:

score: 0
Accepted
time: 4ms
memory: 50560kb

input:

1

output:

0

result:

ok 1 number(s): "0"

Test #5:

score: 0
Accepted
time: 10ms
memory: 50512kb

input:

2
1 2

output:

1

result:

ok 1 number(s): "1"

Test #6:

score: 0
Accepted
time: 7ms
memory: 50432kb

input:

3
2 3
3 1

output:

0

result:

ok 1 number(s): "0"

Test #7:

score: 0
Accepted
time: 4ms
memory: 50432kb

input:

4
2 3
3 1
3 4

output:

0

result:

ok 1 number(s): "0"

Test #8:

score: 0
Accepted
time: 0ms
memory: 50492kb

input:

5
4 2
2 3
4 1
5 3

output:

0

result:

ok 1 number(s): "0"

Test #9:

score: 0
Accepted
time: 4ms
memory: 51744kb

input:

6
4 3
1 4
2 4
5 2
4 6

output:

1

result:

ok 1 number(s): "1"

Test #10:

score: 0
Accepted
time: 4ms
memory: 50564kb

input:

50
21 22
22 27
22 7
22 12
22 13
43 22
36 22
35 22
6 22
10 22
22 38
19 22
34 22
8 22
22 44
22 3
9 22
22 16
23 22
18 22
22 25
22 5
22 2
22 15
46 22
37 22
48 22
33 22
22 17
31 22
22 29
22 28
22 49
4 22
22 26
41 22
22 32
22 50
22 20
22 30
24 22
40 22
22 45
14 22
22 11
42 22
39 22
1 22
47 22

output:

0

result:

ok 1 number(s): "0"

Test #11:

score: 0
Accepted
time: 213ms
memory: 96752kb

input:

1000000
851841 325834
455962 325834
135775 325834
525341 325834
265267 325834
868520 325834
834325 325834
867971 325834
325834 879726
325834 242607
325834 106951
122113 325834
325834 499633
727580 325834
325834 200171
325834 178877
325834 493841
957118 325834
325834 809324
325834 641895
325834 33338...

output:

0

result:

ok 1 number(s): "0"

Test #12:

score: 0
Accepted
time: 7ms
memory: 51148kb

input:

3
2 1
2 3

output:

0

result:

ok 1 number(s): "0"

Test #13:

score: 0
Accepted
time: 8ms
memory: 52464kb

input:

4
4 3
1 4
1 2

output:

1

result:

ok 1 number(s): "1"

Test #14:

score: 0
Accepted
time: 3ms
memory: 50424kb

input:

5
1 4
2 4
3 2
3 5

output:

0

result:

ok 1 number(s): "0"

Test #15:

score: 0
Accepted
time: 7ms
memory: 50556kb

input:

6
3 5
3 6
1 6
1 4
4 2

output:

1

result:

ok 1 number(s): "1"

Test #16:

score: 0
Accepted
time: 0ms
memory: 50500kb

input:

7
1 2
3 2
6 3
6 7
7 4
4 5

output:

0

result:

ok 1 number(s): "0"

Test #17:

score: 0
Accepted
time: 6ms
memory: 50568kb

input:

8
6 2
1 2
8 1
5 8
5 7
7 3
4 3

output:

1

result:

ok 1 number(s): "1"

Test #18:

score: 0
Accepted
time: 6ms
memory: 50432kb

input:

20
6 1
6 15
9 15
18 9
18 17
17 7
8 7
3 8
19 3
2 19
13 2
13 11
12 11
12 14
4 14
4 5
20 5
16 20
16 10

output:

1

result:

ok 1 number(s): "1"

Test #19:

score: 0
Accepted
time: 13ms
memory: 50424kb

input:

42
33 30
17 33
17 7
29 7
15 29
15 23
23 1
10 1
10 31
4 31
12 4
12 34
28 34
28 41
41 11
32 11
32 24
13 24
13 19
26 19
16 26
35 16
35 27
37 27
37 3
3 20
8 20
39 8
6 39
6 42
14 42
14 38
38 9
25 9
18 25
18 5
36 5
36 40
40 21
21 2
22 2

output:

1

result:

ok 1 number(s): "1"

Test #20:

score: -100
Wrong Answer
time: 3ms
memory: 50444kb

input:

27
19 14
6 19
16 19
19 7
19 4
21 19
26 4
26 15
4 5
5 1
10 26
13 26
17 7
3 4
23 13
21 25
2 25
2 12
10 9
20 17
24 16
21 27
22 13
8 16
18 7
11 24

output:

5

result:

wrong answer 1st numbers differ - expected: '6', found: '5'