#include <iostream>
#include <bits/stdc++.h>
using namespace std;
int v[5005],v2[5005],vc[5005],cont[5005],bin[5005],n,j,poz[5005];
ifstream in("secv.in");
ofstream out("secv.out");
int bs(int k){
    int l,r,med=1;
    l=0;
    r=j;
    while(l<=r && vc[med]!=k){
        med=(r+l)/2;
        if(vc[med]<k)
            l=med+1;
        else
            if(vc[med]>k)
                r=med-1;
    }
    if(vc[med]==k)
        return med;
    else
        return -1;
}
int main()
{
    int lc=0,smax=1000000,nr,ci;
    in>>n;
    for(int i=1;i<=n;i++)
        in>>v[i],v2[i]=v[i];
    sort(v2+1,v2+n+1);
    for(int i=1;i<=n;i++)
        if(v2[i]>v2[i-1])
            vc[j++]=v2[i];
    for(int i=1;i<=n;i++)
        bin[i]=bs(v[i]);
    for(int i=1;i<=n;i++){
        if(bin[i]==0){
            int nrd;
            ci=i;
            nr=0;
            lc=1;
            nrd=0;
            while(nrd<=j && i<=n){
                if(bin[i]==nr && poz[bin[i]]==0)
                    nr++,nrd++,poz[bin[i]]=1;
                if(nrd==j)
                    break;
                i++;
                lc++;
            }
            if(lc<smax && nrd==j)
                smax=lc,cout<<ci<<" "<<nrd<<endl;
            memset(poz,0,sizeof(poz));
            i=ci;
        }
    }
    out<<smax;
    return 0;
}