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ID题目提交者结果用时内存语言文件大小提交时间测评时间
#410687#7509. 01treegrass8cowTL 55ms19192kbC++171.5kb2024-05-14 11:23:472024-05-14 11:23:48

Judging History

你现在查看的是最新测评结果

  • [2024-05-14 11:23:48]
  • 评测
  • 测评结果:TL
  • 用时:55ms
  • 内存:19192kb
  • [2024-05-14 11:23:47]
  • 提交

answer

#include<bits/stdc++.h>
using namespace std;
const int N=2e5+10;
int n,fa[N];
vector<int>g[N];
#define pb push_back
char c1[N],c2[N];
const int mod=1e9+7;
int qpow(int a,int b){
    int c=1;
    for(;b;b>>=1){
        if(b&1)c=1ll*a*c%mod;
        a=1ll*a*a%mod;
    }
    return c;
}
int s[N][2][3],jc[N],ij[N],sz[N];
int C(int a,int b){if(a<0||b<0||a<b)return 0;return 1ll*jc[a]*ij[b]%mod*ij[a-b]%mod;}
void doi(){jc[0]=ij[0]=1;for(int i=1;i<=200000;i++)jc[i]=1ll*i*jc[i-1]%mod,ij[i]=qpow(jc[i],mod-2);}
void dfs(int x,int d){
    sz[x]=1;
    for(int v:g[x])if(v!=fa[x]){
        fa[v]=x,dfs(v,d^1),sz[x]+=sz[v];
        for(int i=0;i<2;i++)for(int j=0;j<3;j++)s[x][i][j]+=s[v][i][j];
    }
    if(c1[x]!='?')s[x][0][(c1[x]-'0')^d]++;
    else s[x][0][2]++;
    if(c2[x]!='?')s[x][1][(c2[x]-'0')^d]++;
    else s[x][1][2]++;
}
void sol(){
    scanf("%d",&n);
    for(int i=1;i<=n;i++){
        g[i].clear(),fa[i]=0;
        for(int j=0;j<2;j++)for(int k=0;k<3;k++)s[i][j][k]=0;
    }
    for(int i=1,u,v;i<n;i++)scanf("%d%d",&u,&v),g[u].pb(v),g[v].pb(u);
    scanf("%s%s",c1+1,c2+1);dfs(1,0);
    int ans=0,X=-(s[1][0][1]-s[1][1][2]-s[1][1][1]),E=s[1][0][2]+s[1][1][2];
    if(X<0){puts("0");return;}
    for(int i=2;i<=n;i++){
        int a=s[i][0][1]-s[i][1][2]-s[i][1][1],b=s[i][0][2]+s[i][1][2],B=E-b;
        for(int j=0;j<=b&&j<=X;j++)if(X-j<=E-b)
        (ans+=1ll*C(E-b,X-j)*abs(a+j)%mod*C(b,j)%mod)%=mod;
    }
    printf("%d\n",ans);
}
int main(){
    doi();
    int T;scanf("%d",&T);while(T--)sol();
    return 0;
}

详细

Test #1:

score: 100
Accepted
time: 28ms
memory: 13260kb

input:

3
2
1 2
00
11
3
1 2
2 3
???
???
3
1 2
2 3
??1
0?0

output:

1
16
1

result:

ok 3 number(s): "1 16 1"

Test #2:

score: 0
Accepted
time: 30ms
memory: 13244kb

input:

1000
23
1 2
1 3
1 4
2 5
5 6
4 7
3 8
4 9
8 10
8 11
8 12
1 13
7 14
10 15
7 16
7 17
5 18
18 19
12 20
9 21
21 22
6 23
00?10?0000??1?00111?010
011??1?10?01?110?0??101
6
1 2
1 3
1 4
4 5
3 6
000?10
1???01
25
1 2
2 3
2 4
4 5
5 6
2 7
4 8
5 9
7 10
8 11
11 12
5 13
11 14
3 15
6 16
14 17
1 18
4 19
6 20
4 21
5 22...

output:

53545
24
11724
2228
162
14
711
28
550
1680
52
2
13
988
9480
2342
626416
0
71780
1
88
39207
19448
4
37395
9602
3253496
38057200
1066
3
303732
1608
281022
11718
170
78
15
1219376
29364
9092
7
0
2
7014
1942448
170371
75845
167217
16554
64
904
564290
14822
1127090
1758504
1227646
14833316
14954550
36055...

result:

ok 1000 numbers

Test #3:

score: 0
Accepted
time: 29ms
memory: 13244kb

input:

1
3000
1 2
2 3
2 4
1 5
3 6
2 7
5 8
8 9
9 10
10 11
2 12
11 13
7 14
11 15
7 16
13 17
8 18
1 19
11 20
10 21
18 22
7 23
7 24
15 25
23 26
24 27
14 28
15 29
25 30
16 31
6 32
10 33
3 34
30 35
16 36
9 37
36 38
28 39
26 40
33 41
1 42
11 43
20 44
23 45
14 46
31 47
41 48
11 49
48 50
45 51
6 52
10 53
32 54
38 5...

output:

924036898

result:

ok 1 number(s): "924036898"

Test #4:

score: 0
Accepted
time: 28ms
memory: 13312kb

input:

1
3000
1 2
1 3
2 4
2 5
3 6
3 7
4 8
4 9
5 10
5 11
6 12
6 13
7 14
7 15
8 16
8 17
9 18
9 19
10 20
10 21
11 22
11 23
12 24
12 25
13 26
13 27
14 28
14 29
15 30
15 31
16 32
16 33
17 34
17 35
18 36
18 37
19 38
19 39
20 40
20 41
21 42
21 43
22 44
22 45
23 46
23 47
24 48
24 49
25 50
25 51
26 52
26 53
27 54
2...

output:

429465738

result:

ok 1 number(s): "429465738"

Test #5:

score: 0
Accepted
time: 44ms
memory: 14456kb

input:

1
3000
1 2
2 3
3 4
4 5
5 6
6 7
7 8
8 9
9 10
10 11
11 12
12 13
13 14
14 15
15 16
16 17
17 18
18 19
19 20
20 21
21 22
22 23
23 24
24 25
25 26
26 27
27 28
28 29
29 30
30 31
31 32
32 33
33 34
34 35
35 36
36 37
37 38
38 39
39 40
40 41
41 42
42 43
43 44
44 45
45 46
46 47
47 48
48 49
49 50
50 51
51 52
52 5...

output:

650625747

result:

ok 1 number(s): "650625747"

Test #6:

score: 0
Accepted
time: 55ms
memory: 19192kb

input:

1
100000
1 2
1 3
3 4
1 5
2 6
6 7
2 8
1 9
6 10
1 11
3 12
11 13
5 14
9 15
12 16
6 17
13 18
13 19
14 20
7 21
14 22
21 23
12 24
17 25
14 26
3 27
4 28
8 29
22 30
12 31
6 32
30 33
4 34
15 35
12 36
3 37
20 38
7 39
37 40
5 41
13 42
34 43
9 44
27 45
39 46
43 47
3 48
17 49
36 50
12 51
1 52
45 53
35 54
15 55
2...

output:

143309878

result:

ok 1 number(s): "143309878"

Test #7:

score: 0
Accepted
time: 41ms
memory: 17100kb

input:

1
100000
1 2
1 3
2 4
2 5
3 6
3 7
4 8
4 9
5 10
5 11
6 12
6 13
7 14
7 15
8 16
8 17
9 18
9 19
10 20
10 21
11 22
11 23
12 24
12 25
13 26
13 27
14 28
14 29
15 30
15 31
16 32
16 33
17 34
17 35
18 36
18 37
19 38
19 39
20 40
20 41
21 42
21 43
22 44
22 45
23 46
23 47
24 48
24 49
25 50
25 51
26 52
26 53
27 54...

output:

724432513

result:

ok 1 number(s): "724432513"

Test #8:

score: -100
Time Limit Exceeded

input:

1
100000
1 2
2 3
3 4
4 5
5 6
6 7
7 8
8 9
9 10
10 11
11 12
12 13
13 14
14 15
15 16
16 17
17 18
18 19
19 20
20 21
21 22
22 23
23 24
24 25
25 26
26 27
27 28
28 29
29 30
30 31
31 32
32 33
33 34
34 35
35 36
36 37
37 38
38 39
39 40
40 41
41 42
42 43
43 44
44 45
45 46
46 47
47 48
48 49
49 50
50 51
51 52
52...

output:


result: