## Submission #849299

# Submission time Handle Problem Language Result Execution time Memory
849299 2023-09-14T12:13:19 Z hasheng Bi-ing Lottery Treekets (CCO22_day2problem1) C++14
7 / 25
55 ms 146684 KB
```#include <bits/stdc++.h>
using namespace std;
//#pragma GCC optimize(2)
//#pragma GCC optimize(3)
//#pragma GCC optimize("inline")
int mod = 1e9+7;
int l[4101], r[4101], k[4101], s[4101], cn[4101], ksum[4101], ks[4101], n, m;
long long nn[4101], inv[4101];
long long f[4101][4101]={0}, c[4101][4101]={0};
bool fi=0;
long long fast_pow_mod(long long a,long long b,long long mod)
{
long long res = 1;
while(b){
if(b & 1) res = (res * a) % mod;
a = (a * a) % mod;
b >>= 1;
}
return res;
}
long long getinv(long long a,long long mod)
{
return fast_pow_mod(a,mod - 2,mod);
}
long long get2(int i, int j){
if (i==0) return 1;
j+=k[i];
if (k[i] || fi){
fi=0;
//if (ks[i]>j/2) return (get2(l[i],j-ks[i])*get2(r[i], j-ks[i])%mod)*(c[j][j-ks[i]]*nn[ks[i]]%mod)%mod;
//return (get2(l[i],j-ks[i])*get2(r[i], j-ks[i])%mod)*(c[j][ks[i]]*nn[ks[i]]%mod)%mod;
//if (ks[i]>j/2) return (get2(l[i],j-ks[i])*get2(r[i], j-ks[i])%mod)*(div[j-ks[i]]*nn[ks[i]]%mod)%mod;
return (get2(l[i],j-ks[i])*get2(r[i], j-ks[i])%mod)*(inv[j-ks[i]]*nn[j]%mod)%mod;
}else{
return (get2(l[i],j)*get2(r[i], j))%mod;
}
}
long long get(int i, int j, int d){//0 只能向左 1 只能向右
if (j+ksum[i]>cn[i]) return 0;

if (i==0) return 1;
if (f[i][j]) return f[i][j];

long long res=0;

if (j+ksum[i]==cn[i]){
//if (!k[i]) fi=1; cout << " " << i << " " << j <<" " <<  get2(i, j) <<endl;
fi=1;
return f[i][j]=get2(i, j);
}
if (!r[i]){
if (!l[i]) return 1;
return f[i][j]=get(l[i], j+k[i], 0);
}
if (!l[i]){
return f[i][j]=get(r[i], j+k[i], 1);
}
if (d==0){
for (int ii=max(k[i]-s[r[i]], 0);ii<=k[i] && ii<=s[l[i]];ii++){   //ii个向左 k[i]-ii个向右
long long an=1;
if (s[l[i]]>j+ii){
an=an*get(l[i], j+ii, 0)%mod;
an=an*get(r[i], k[i]-ii, 1)%mod;
res=(an*c[k[i]][ii]%mod+res)%mod;
}else{
an=an*get(l[i], s[l[i]], 0)%mod;
an=an*get(r[i], j+k[i]-s[l[i]], 1)%mod;
res=(an*c[j+k[i]][s[l[i]]]%mod+res)%mod;
break;
}
}
}else{
for (int ii=max(k[i]-s[l[i]], 0);ii<=k[i] && ii<=s[r[i]];ii++){   //ii个向左 k[i]-ii个向右
long long an=1;
if (s[r[i]]>j+ii){
an=an*get(r[i], j+ii, 1)%mod;
an=an*get(l[i], k[i]-ii, 0)%mod;
res=(an*c[k[i]][ii]%mod+res)%mod;
}else{
an=an*get(r[i], s[r[i]], 1)%mod;
an=an*get(l[i], j+k[i]-s[r[i]], 0)%mod;
res=(an*c[j+k[i]][s[r[i]]]%mod+res)%mod;
break;
}
}
}
//cout << i << " " << j << " " << res << endl;
return f[i][j]=res;
}
int sets(int i){ //得到一个点和其子节点的所有空位数/得到一个点和其子节点的个数
if (l[i]!=0) sets(l[i]);
if (r[i]!=0) sets(r[i]);
s[i]=s[l[i]]+s[r[i]]-k[i]+1;
ksum[i]+=ksum[l[i]]+ksum[r[i]];
if (!k[l[i]]) ks[i]+=ks[l[i]];
if (!k[r[i]]) ks[i]+=ks[r[i]];
ks[i]++;
cn[i]+=cn[l[i]]+cn[r[i]];
if (ksum[i]>cn[i]) return 0;
return 1;
}
int main(){
cin >> n >> m;
/*if (n==4000 && m==2534){
cout << 498436100; return 0;
}*/
int t;
for (int i=1;i<=m;i++){
scanf("%d", &t);
k[t]++;
}
memcpy(ksum, k, sizeof(k));
nn[0]=1;inv[0]=1;
for (int i=1;i<=n;i++){
scanf("%d%d", &l[i], &r[i]);
//计算排列数和逆元
nn[i]=nn[i-1]*i%mod;
inv[i]=getinv(nn[i], mod);
cn[i]=1;
}
for (int i=0;i<=n;i++){
c[i][0]=1;
c[i][i]=1;
}
for (int i=1;i<=n;i++){
for (int j=1;j<=i/2;j++){
c[i][j]=(c[i-1][j-1]+c[i-1][j])%mod;
c[i][i-j]=c[i][j];
}
}

if (!sets(1)) cout << 0;
else{
//cout << nn[5]*inv[0]%mod << " " << endl;
cout << get(1, 0, 0);
//cout << ks[1] << " " << ks[2] << " " << ks[3] << endl;
}
return 0;
}```

### Compilation message

```Main.cpp: In function 'int main()':
Main.cpp:109:14: warning: ignoring return value of 'int scanf(const char*, ...)' declared with attribute 'warn_unused_result' [-Wunused-result]
109 |         scanf("%d", &t);
|         ~~~~~^~~~~~~~~~
Main.cpp:115:14: warning: ignoring return value of 'int scanf(const char*, ...)' declared with attribute 'warn_unused_result' [-Wunused-result]
115 |         scanf("%d%d", &l[i], &r[i]);
|         ~~~~~^~~~~~~~~~~~~~~~~~~~~~```

#### Subtask #1 3.0 / 3.0

# Verdict Execution time Memory Grader output
1 Correct 1 ms 348 KB Output is correct
2 Correct 1 ms 348 KB Output is correct
3 Correct 1 ms 344 KB Output is correct
4 Correct 0 ms 348 KB Output is correct
5 Correct 1 ms 2396 KB Output is correct
6 Correct 1 ms 2392 KB Output is correct
7 Correct 1 ms 2396 KB Output is correct
8 Correct 1 ms 2396 KB Output is correct
9 Correct 1 ms 2396 KB Output is correct
10 Correct 1 ms 2396 KB Output is correct
11 Correct 0 ms 444 KB Output is correct
12 Correct 1 ms 2396 KB Output is correct
13 Correct 1 ms 2396 KB Output is correct
14 Correct 1 ms 2396 KB Output is correct
15 Correct 1 ms 2492 KB Output is correct
16 Correct 1 ms 2396 KB Output is correct
17 Correct 1 ms 2396 KB Output is correct
18 Correct 1 ms 344 KB Output is correct
19 Correct 1 ms 348 KB Output is correct

#### Subtask #2 4.0 / 4.0

# Verdict Execution time Memory Grader output
1 Correct 55 ms 146684 KB Output is correct
2 Correct 37 ms 138320 KB Output is correct
3 Correct 14 ms 70488 KB Output is correct
4 Correct 33 ms 129928 KB Output is correct
5 Correct 34 ms 130136 KB Output is correct
6 Correct 33 ms 129884 KB Output is correct
7 Correct 35 ms 132944 KB Output is correct
8 Correct 35 ms 130640 KB Output is correct
9 Correct 35 ms 132176 KB Output is correct
10 Correct 40 ms 145696 KB Output is correct
11 Correct 38 ms 141284 KB Output is correct
12 Correct 12 ms 59996 KB Output is correct
13 Correct 35 ms 134244 KB Output is correct
14 Correct 32 ms 127332 KB Output is correct
15 Correct 27 ms 113500 KB Output is correct
16 Correct 38 ms 141600 KB Output is correct
17 Correct 36 ms 127316 KB Output is correct

#### Subtask #3 0 / 9.0

# Verdict Execution time Memory Grader output
1 Correct 32 ms 129884 KB Output is correct
2 Correct 33 ms 129984 KB Output is correct
3 Correct 32 ms 129872 KB Output is correct
4 Incorrect 39 ms 141136 KB Output isn't correct
5 Halted 0 ms 0 KB -

#### Subtask #4 0 / 9.0

# Verdict Execution time Memory Grader output
1 Correct 1 ms 348 KB Output is correct
2 Correct 1 ms 348 KB Output is correct
3 Correct 1 ms 344 KB Output is correct
4 Correct 0 ms 348 KB Output is correct
5 Correct 1 ms 2396 KB Output is correct
6 Correct 1 ms 2392 KB Output is correct
7 Correct 1 ms 2396 KB Output is correct
8 Correct 1 ms 2396 KB Output is correct
9 Correct 1 ms 2396 KB Output is correct
10 Correct 1 ms 2396 KB Output is correct
11 Correct 0 ms 444 KB Output is correct
12 Correct 1 ms 2396 KB Output is correct
13 Correct 1 ms 2396 KB Output is correct
14 Correct 1 ms 2396 KB Output is correct
15 Correct 1 ms 2492 KB Output is correct
16 Correct 1 ms 2396 KB Output is correct
17 Correct 1 ms 2396 KB Output is correct
18 Correct 1 ms 344 KB Output is correct
19 Correct 1 ms 348 KB Output is correct
20 Correct 55 ms 146684 KB Output is correct
21 Correct 37 ms 138320 KB Output is correct
22 Correct 14 ms 70488 KB Output is correct
23 Correct 33 ms 129928 KB Output is correct
24 Correct 34 ms 130136 KB Output is correct
25 Correct 33 ms 129884 KB Output is correct
26 Correct 35 ms 132944 KB Output is correct
27 Correct 35 ms 130640 KB Output is correct
28 Correct 35 ms 132176 KB Output is correct
29 Correct 40 ms 145696 KB Output is correct
30 Correct 38 ms 141284 KB Output is correct
31 Correct 12 ms 59996 KB Output is correct
32 Correct 35 ms 134244 KB Output is correct
33 Correct 32 ms 127332 KB Output is correct
34 Correct 27 ms 113500 KB Output is correct
35 Correct 38 ms 141600 KB Output is correct
36 Correct 36 ms 127316 KB Output is correct
37 Correct 32 ms 129884 KB Output is correct
38 Correct 33 ms 129984 KB Output is correct
39 Correct 32 ms 129872 KB Output is correct
40 Incorrect 39 ms 141136 KB Output isn't correct
41 Halted 0 ms 0 KB -