#include <bits/stdc++.h>
using namespace std;
#define int                     long long   
#define double                  long double
#define endl                    "\n"
#define pb                      push_back
#define PI                      3.1415926535897932384626433832795l
#define F                       first
#define S                       second
#define mp                      make_pair
#define f(i,n)                  for(int i=0;i<n;i++)
#define fastio                  ios::sync_with_stdio(0);cin.tie(0);cout.tie(0);
#define all(v)                  (v).begin(),(v).end()
#define rall(v)                 (v).rbegin(),(v).rend()
#define gcd(a,b)                __gcd((a),(b))
#define fill(a,value)           memset(a,value,sizeof(a));
#define minn(v)                 *min_element(v.begin(), v.end());
#define maxx(v)                 *max_element(v.begin(), v.end());
#define print(x)                cout<<(x)<<endl;
#define sum(v)+x                accumulate(v.begin(), v.end(),x);
#define debug(x)                cout<<#x<<'='<<(x)<<endl;
typedef pair<int,int>           pii;
typedef vector<int>             vi;
const int MAX = 1000001; 
  
// structure to store queries 
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;
} 
signed main() 
{
    fastio;
    cout << fixed << setprecision(12);
    int n,q;
    cin>>n>>q;
    int a[n];
    f(i,n)cin>>a[i];
    Query queries[q]; 
    f(i,q)
    {
        int x,y;
        cin>>x>>y;
        x--;
        y--;
        queries[i].l = x; 
        queries[i].r = y; 
        queries[i].idx = i; 
    }
    sort(queries, queries+q, cmp); 
    answeringQueries(a, n, queries, q);
    return 0;
}


Measured memory_bytes: 35088