368B.cpp

/******************************************
*******************************************
*******************************************
	PREPARED BY - SOMESH AWASTHI 
	CHANDIGARH UNIVERSITY
*******************************************
*******************************************
*******************************************/

#include<bits/stdc++.h>
using namespace std;
#define fr(i,a,b) for(long long i=a;i<b;i++)
#define io ios::sync_with_stdio(false);cin.tie(NULL);
typedef long long ll;
typedef unsigned long long ull;
typedef pair<int,int> pii;
typedef pair<ll,ll> pll;
typedef vector<int> vi;
typedef vector<ll> vl;
long int mod=1000000007;

int main()
{
	io
	#ifdef SOMU
		clock_t startTime = clock();
		freopen("input.txt","r",stdin);
	#endif

	int n, m;
	cin >> n >> m;
	vi arr(n);
	fr(i,0,n){
		cin >> arr[i];
	}
	vi ans(n, 0);
	unordered_set<int> s;
	for(int i = n - 1; i >= 0; i--){
		s.insert(arr[i]);
		ans[i] = s.size();
	}
	while(m--){
		int x;
		cin >> x;
		cout<<ans[x - 1]<<'\n';	
	}

	#ifdef SOMU
		cout << endl <<setprecision(20)<< double( clock() - startTime ) / (double)CLOCKS_PER_SEC<< " seconds." << endl;
	#endif
	return 0;
}