#include <bits/stdc++.h>
#include <ext/pb_ds/tree_policy.hpp>
#include <ext/pb_ds/assoc_container.hpp>

#define endl "\n"
#define int ll
#define ll long long
#define pb emplace_back
#define fi first
#define se second
#define pll pair<ll, ll>
#define ull unsigned long long
#define ld long double

#define debug(x) cout<<#x<<" :: "<<x<<endl;
#define debug2(x,y) cout<<#x<<" :: "<<x<<"\t"<<#y<<" :: "<<y<<endl;
#define debug3(x,y,z) cout<<#x<<" :: "<<x<<"\t"<<#y<<" :: "<<y<<"\t"<<#z<<" :: "<<z<<endl;

#define all(x) (x).begin(), (x).end()
#define ordered_set tree<int , null_type, less<int> , rb_tree_tag, tree_order_statistics_node_update>
/*
 Ordered set docs:
 order_of_key (k) : Number of items strictly smaller than k .
 find_by_order(k) : K-th element in a set (counting from zero).
*/
#define blc boost::lexical_cast<long long>
#define fast ios_base::sync_with_stdio(false);cin.tie(NULL);cout.tie(NULL)
using namespace std;
using namespace __gnu_pbds;
const int MOD = 1e9+7;
const int MAX = 5e5+4;
ll add(ll x, ll y) {ll res=x+y; return(res>=MOD?res-MOD:res);}

ll sub(ll x, ll y) {ll res=x-y; return(res<0?res+MOD:res);}

ll lcm(ll x, ll y) {ll res=(x*y)/__gcd(x,y); return res;}

ll powerLL(ll x, ll n, ll mod) 
{ 
    ll result = 1; 
    while (n) { if (n & 1) result = (result%mod * x%mod) % mod; n = n / 2; x = (x%mod * x%mod) % mod; } return result; 
} 

//////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////

struct Query 
{ 
    int l, r, idx; 
}; 
  
// cmp function to sort queries according to r 
bool cmp(Query x, Query y) 
{ 
    return x.r < y.r; 
} 
  
// updating the bit array 
void update(int idx, int val, int bit[], int n) 
{ 
    for (; idx <= n; idx += idx&-idx) 
        bit[idx] += val; 
} 
  
// querying the bit array 
int query(int idx, int bit[], int n) 
{ 
    int sum = 0; 
    for (; idx>0; idx-=idx&-idx) 
        sum += bit[idx]; 
    return sum; 
} 
  
void answeringQueries(int arr[], int n, Query queries[], int q) 
{ 
    // initialising bit array 
    int bit[n+1]; 
    memset(bit, 0, sizeof(bit)); 
  
    // holds the rightmost index of any number 
    // as numbers of a[i] are less than or equal to 10^6 
    int last_visit[MAX]; 
    memset(last_visit, -1, sizeof(last_visit)); 
  
    // answer for each query 
    int ans[q]; 
    int query_counter = 0; 
    for (int i=0; i<n; i++) 
    { 
        // If last visit is not -1 update -1 at the 
        // idx equal to last_visit[arr[i]] 
        if (last_visit[arr[i]] !=-1) 
            update (last_visit[arr[i]] + 1, -1, bit, n); 
  
        // Setting last_visit[arr[i]] as i and updating 
        // the bit array accordingly 
        last_visit[arr[i]] = i; 
        update(i + 1, 1, bit, n); 
  
        // If i is equal to r of any query  store answer 
        // for that query in ans[] 
        while (query_counter < q && queries[query_counter].r == i) 
        { 
            ans[queries[query_counter].idx] = 
                     query(queries[query_counter].r + 1, bit, n)- 
                     query(queries[query_counter].l, bit, n); 
            query_counter++; 
        } 
    } 
  
    // print answer for each query 
    for (int i=0; i<q; i++) 
        cout << ans[i] << endl; 
} 

void solve()
{
    ll n, q;
    cin>>n>>q;
    int a[n];
    for(ll i=0; i<n; i++)
    	cin>>a[i];
    Query que[q];
    for(ll i=0; i<q; i++)
	{
		ll x,y;
		cin>>x>>y;
		que[i].l = x-1;
		que[i].r = y-1;
		que[i].idx = i;
	}
    sort(que, que+q, cmp);
    answeringQueries(a, n, que, q);
}
int32_t main()
{
    fast;
    int t;
    t=1;
    //cin>>t;
    while(t--)
        solve();
    return 0; 
}

Measured memory_bytes: 31160