이거 맞나????????

combifnd.cpp

#include<iostream>
#include<vector>
using namespace std;
using ll=long long;

const ll mod=10007;

ll mod_pow(int a,int n,int p)
{
    ll ret=1;
    ll A=a;
    while(n)
    {
        if (n & 1)
            ret=(ret*A)%p;
        A=(A*A)%p;
        n>>=1;
    }
    return ret;
}

ll factorial[mod];

void init(ll p)
{
    factorial[0] = 1;
    for(int i = 1;i <= p;i++)
        factorial[i] = factorial[i-1]*i%p;
}

ll C(ll a,ll k,ll p) 
{
    ll re = 1;
    while(a && k)
    {
        ll aa = a%p;ll bb = k%p;
        if(aa < bb) return 0; 
        re = re*factorial[aa]*mod_pow(factorial[bb]*factorial[aa-bb]%p,p-2,p)%p;
        a /= p;
        k /= p;
    }
    return re;
}

int n,k;
vector<int> res;
int t;

ll count(int curr, int idx, int p)
{
	if(idx==k-1&&res[idx]==curr)return 1;
	if(curr==res[idx])
	{
		return count(curr+1,idx+1,p)%p;
	}
	else
	{
		return (C(n-curr+1,k-idx-1,p)+count(curr+1,idx,p))%p;
	}
}

int main()
{
	init(mod);
	cin>>n>>k;
	res.resize(k);
	for(int&i:res)cin>>i;
	cout<<count(1,0,mod);
}