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QOJ
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. 01tree | grass8cow | TL | 55ms | 19192kb | C++17 | 1.5kb | 2024-05-14 11:23:47 | 2024-05-14 11:23:48 |
Judging History
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...