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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 |
|---|---|---|---|---|---|---|---|---|---|
| #571780 | #9353. Interesting Permutation | huaxiamengjin | RE | 0ms | 5220kb | C++14 | 726b | 2024-09-18 08:34:42 | 2024-09-18 08:34:42 |
Judging History
answer
#include<bits/stdc++.h>
using namespace std;
#define int long long
const int NN=1e9+7;
int p[100100],ni[100100];
int n,a[100100];
int mi(int x,int y){
int sum=1;
for (;y;y>>=1,x=x*x%NN)
if(y&1)sum=sum*x%NN;
return sum;
}
int c(int x,int y){
if(x<0||y<0||x<y)return 0;
return p[x]*ni[x-y]%NN;
}
void solve(){
cin>>n;
for (int i=1;i<=n;i++)
cin>>a[i];
int pre=n-1;
int ans=1;
for (int i=n;i>=1;i--){
if(a[i]!=pre){
ans=ans*2%NN*c(pre-i,pre-a[i]-1)%NN;
pre=a[i];
}
}
cout<<ans<<"\n";
}
signed main(){
int N=1e5;
p[0]=1;
for (int i=1;i<=N;i++)
p[i]=p[i-1]*i%NN;
ni[N]=mi(p[N],NN-2);
for (int i=N;i;i--)
ni[i-1]=ni[i]*i%NN;
int T;cin>>T;
while(T--)solve();
}
詳細信息
Test #1:
score: 100
Accepted
time: 0ms
memory: 5220kb
input:
3 3 0 2 2 3 0 1 2 3 0 2 3
output:
2 4 0
result:
ok 3 lines
Test #2:
score: -100
Runtime Error
input:
10039 14 5 6 7 8 9 10 11 12 13 13 13 13 13 13 14 0 5 6 7 8 9 10 11 12 13 14 14 14 14 1 1 14 0 5 4 8 9 10 11 12 13 13 13 13 13 13 45 0 1 1 2 2 3 5 5 6 6 8 9 11 13 15 17 18 18 20 22 22 24 26 26 26 26 27 27 27 28 30 32 32 33 34 34 34 36 36 38 38 38 39 39 44 24 0 2 3 5 7 9 9 10 11 12 13 14 14 14 14 15 1...
output:
256 0 0 0 0 0 24576 0 0 0 0 0 658159182 0 805306368 8 572589350 12288 2 0 981283070 0 0 2 0 0 0 0 4423680 0 0 14155776 16 0 768 0 0 0 855189487 0 2 0 0 0 0 2 0 2 797370259 0 0 0 0 4 0 0 0 301989888 0 0 0 0 0 0 0 0 0 0 0 0 0 2 0 0 0 0 192 0 0 12288 0 0 2 8 0 0 495514526 0 0 955131071 768 0 0 147456 0...