#include <bits/stdc++.h>
using namespace std;
#define LOCAL
#pragma region Macros
typedef long long ll;
#define ALL(x) (x).begin(),(x).end()
const long long MOD=1e9+7;
// const long long MOD=998244353;
const int INF=1e9;
const long long IINF=1e18;
const int dx[4]={1,0,-1,0},dy[4]={0,1,0,-1};
const char dir[4]={'D','R','U','L'};

template<typename T>
istream &operator>>(istream &is,vector<T> &v){
    for (T &x:v) is >> x;
    return is;
}
template<typename T>
ostream &operator<<(ostream &os,const vector<T> &v){
    for (int i=0;i<v.size();++i){
        os << v[i] << (i+1==v.size()?"": " ");
    }
    return os;
}
template<typename T,typename U>
ostream &operator<<(ostream &os,const pair<T,U> &p){
    cout << '(' << p.first << ',' << p.second << ')';
    return os;
}
template<typename T,typename U>
ostream &operator<<(ostream &os,const map<T,U> &m){
    os << '{';
    for (auto itr=m.begin();itr!=m.end();++itr){
        os << '(' << itr->first << ',' << itr->second << ')';
        if (++itr!=m.end()) os << ',';
        --itr;
    }
    os << '}';
    return os;
}
template<typename T>
ostream &operator<<(ostream &os,const set<T> &s){
    os << '{';
    for (auto itr=s.begin();itr!=s.end();++itr){
        os << *itr;
        if (++itr!=s.end()) os << ',';
        --itr;
    }
    os << '}';
    return os;
}

void debug_out(){cerr << '\n';}
template<class Head,class... Tail>
void debug_out(Head&& head,Tail&&... tail){
    cerr << head;
    if (sizeof...(Tail)>0) cerr << ", ";
    debug_out(move(tail)...);
}
#ifdef LOCAL
#define debug(...) cerr << " ";\
cerr << #__VA_ARGS__ << " :[" << __LINE__ << ":" << __FUNCTION__ << "]" << '\n';\
cerr << " ";\
debug_out(__VA_ARGS__)
#else
#define debug(...) 42
#endif

template<typename T> T gcd(T x,T y){return y!=0?gcd(y,x%y):x;}
template<typename T> T lcm(T x,T y){return x/gcd(x,y)*y;}

template<class T1,class T2> inline bool chmin(T1 &a,T2 b){
    if (a>b){a=b; return true;} return false;
}
template<class T1,class T2> inline bool chmax(T1 &a,T2 b){
    if (a<b){a=b; return true;} return false;
}
#pragma endregion

template<typename T>
struct BinaryIndexedTree{
    vector<T> dat;
    BinaryIndexedTree(int n):dat(n+1,0){}
    void add(int i,T x){
        if (i==0) return;
        for (;i<=dat.size();i+=(i&-i)) dat[i]+=x;
    }
    T sum(int i){
        T res=0;
        for (;i>0;i-=(i&-i)) res+=dat[i];
        return res;
    }
    T query(int l,int r){ //[l,r)
        return sum(r-1)-sum(l-1);
    }
    int lower_bound(T x){
        if (x<=0) return 0;
        int lb=0,r=1;
        while(r<dat.size()) r<<=1;
        for (;r>0;r>>=1){
            if (lb+r<dat.size()&&dat[lb+r]<x){
                x-=dat[lb+r]; lb+=r;
            }
        }
        return lb+1;
    }
    void add0(int i,T x){add(i+1,x);}
    T sum0(int i){return sum(i+1);}
    T query0(int l,int r){return sum(r)-sum(l);}
};

int main(){
    cin.tie(0);
    ios::sync_with_stdio(false);
    int N,Q; cin >> N >> Q;
    vector<int> c(N);
    for (int i=0;i<N;++i) cin >> c[i],--c[i];
    struct seg{
        int l,r,id;
        seg(int l,int r,int id):l(l),r(r),id(id){}
        const bool operator<(const seg &rhs){
            return r<rhs.r;
        }
    };
    vector<seg> S;
    for (int i=0;i<Q;++i){
        int l,r; cin >> l >> r;
        S.emplace_back(--l,r,i);
    }
    sort(ALL(S));
    BinaryIndexedTree<int> BIT(N);
    int now=0;
    vector<int> pre(N,-1),ans(Q);
    for (int i=0;i<Q;++i){
        int l=S[i].l,r=S[i].r;
        while(now<N&&now<r){
            if (~pre[c[now]]) BIT.add0(pre[c[now]],-1);
            BIT.add0(now,1);
            pre[c[now]]=now; ++now;
        }
        ans[S[i].id]=BIT.query0(l,r);
    }
    for (int i=0;i<Q;++i) cout << ans[i] << '\n';
}

Measured memory_bytes: 17456