#include <iostream>
#include <cstring>
#define MAXN 2005

using namespace std;

int n, q, l, r;
int a[MAXN];

bool A(int h[], int b[]){

    /*for(int i = 0; i <= 20; i++){
        cout << h[i] << ' ';
    }
    cout << "-------------";
    for(int i = 0; i <= 20; i++){
        cout << b[i] << ' ';
    }
    cout << "---------------";

    cout << endl ;*/

    for(int i = 0; i <= 20; i++){
        if(h[i] > 0 && b[i] == 0)return 0;
    }
    return 1;
}

int main(){
    cin >> n >> q;
    for(int i = 1; i <= n; i++){
        cin >> a[i];
    }
    for(int i = 1; i <= q; i++){
        int h[MAXN], b[MAXN];
        memset(h, 0, sizeof(h));
        memset(b, 0, sizeof(b));
        int ans = MAXN;
        cin >> l >> r;
        for(int j = l; j <= r; j++){
            h[a[j]]++;
        }
        b[a[l]]++;
        int x = l, y = l;
        //cout << 666;
        while(x <= r && y <= r){
            while(A(h, b) == 0 && y <= r){
                y++;
                b[a[y]]++;
            }

            if(A(h, b)){
                //cout << 666;
                ans = min(ans, y - x + 1);
            }
            //cout << 777;
            while(A(h, b) && x <= y){
                b[a[x]]--;
                x++;
                if(A(h, b)){
                    //cout << 666;
                    ans = min(ans, y - x + 1);
                }
            }

        }
        cout << ans << endl;
    }
    return 0;
}