#include <bits/stdc++.h>
using namespace std;
const int N=2e5+5,MOD=1e9+7;
int n,k;
int arr[N],ans[N];
int l[N],r[N];
stack<int> ll,rr;
vector<int> del[N];
long long fac[N],infac[N],anss;
long long poww(long long x,long long y)
{
if(y==0) return 1;
if(y&1) return (poww(x,y-1)*x)%MOD;
return poww((x*x)%MOD,y/2);
}
long long nCk(int n,int k)
{
return (((fac[n]*infac[k])%MOD)*infac[n-k])%MOD;
}
void add(int x,int dl,int dr)
{
//cout << l[x]+r[x] << " " << l[x] << " " << poww(nCk(l[x]+r[x],l[x]),MOD-2) << endl;
anss=(anss*poww(nCk(l[x]+r[x],l[x]),MOD-2))%MOD;
l[x]+=dl; r[x]+=dr;
//cout << l[x]+r[x] << " " << l[x] << " " << nCk(l[x]+r[x],l[x]) << endl;
anss=(anss*nCk(l[x]+r[x],l[x]))%MOD;
}
int main()
{
fac[0]=infac[0]=1; anss=1;
for(int i=1;i<N;i++) {fac[i]=(i*fac[i-1])%MOD; infac[i]=poww(fac[i],MOD-2);}
scanf("%d %d",&n,&k);
for(int i=0;i<n;i++)
scanf("%d",&arr[i]);
for(int i=n-1;i>0;i--)
{
r[arr[i]]++;
while(rr.size() && rr.top()>arr[i])
{
del[i].push_back(rr.top());
r[rr.top()]--;
rr.pop();
}
rr.push(arr[i]);
}
ans[0]=1;
for(int i=1;i<n;i++)
{
while(ll.size() && ll.top()>arr[i-1])
{
add(ll.top(),-1,0);
ll.pop();
}
ll.push(arr[i-1]);
add(arr[i-1],1,0);
add(rr.top(),0,-1);
rr.pop();
for(int j=0;j<del[i].size();j++)
{
rr.push(del[i][j]);
add(del[i][j],0,1);
}
ans[i]=anss;
}
while(k--)
{
int x;
scanf("%d",&x);
x--;
printf("%d\n",ans[x]);
}
}
Compilation message
zarulje.cpp: In function 'int main()':
zarulje.cpp:65:16: warning: comparison between signed and unsigned integer expressions [-Wsign-compare]
for(int j=0;j<del[i].size();j++)
~^~~~~~~~~~~~~~
zarulje.cpp:39:7: warning: ignoring return value of 'int scanf(const char*, ...)', declared with attribute warn_unused_result [-Wunused-result]
scanf("%d %d",&n,&k);
~~~~~^~~~~~~~~~~~~~~
zarulje.cpp:41:8: warning: ignoring return value of 'int scanf(const char*, ...)', declared with attribute warn_unused_result [-Wunused-result]
scanf("%d",&arr[i]);
~~~~~^~~~~~~~~~~~~~
zarulje.cpp:75:8: warning: ignoring return value of 'int scanf(const char*, ...)', declared with attribute warn_unused_result [-Wunused-result]
scanf("%d",&x);
~~~~~^~~~~~~~~
# |
결과 |
실행 시간 |
메모리 |
Grader output |
1 |
Incorrect |
50 ms |
8312 KB |
Output isn't correct |
2 |
Halted |
0 ms |
0 KB |
- |
# |
결과 |
실행 시간 |
메모리 |
Grader output |
1 |
Incorrect |
162 ms |
11000 KB |
Output isn't correct |
2 |
Halted |
0 ms |
0 KB |
- |
# |
결과 |
실행 시간 |
메모리 |
Grader output |
1 |
Incorrect |
50 ms |
8312 KB |
Output isn't correct |
2 |
Halted |
0 ms |
0 KB |
- |