#include<iostream>
#include<algorithm> 
#include<cstring>
#include<queue>

using namespace std;

typedef pair<int , int > PII ;
const int N = 200010, M = 3*N ;
int h[N] , e[M] , ne[M] , idx = 0 , n;
PII a[N] ;
int dis[N] ;
bool st[N] ;

void insert( int  a , int b)//wu
{
    e[idx] = b;
    ne[idx] = h[a];
    h[a] = idx ++ ;
}

int bfs()
{
    memset (dis , -1 , sizeof dis ) ;
    dis [1] = 0 ;
    
    queue <int> q ;
    
    q.push(1) ;
    
    st[1] = true ;
    while(q.size())//bfs经典代码，路径最短的就会先到
    {
        auto t = q.front();
        q.pop() ;
        
        for(int i = h[t];i != -1;i = ne[i])
        {
            int j = e[i] ;
            if( !st[j] )
            {
                dis[j] = dis[t] + 1 ;
                q.push(j) ;
                st[j] = true ;
            }
        }    
    }
    return dis[n];
    
}



int main( )
{
    memset(h , -1 , sizeof h) ; 
    
    cin >> n ; 
    
    for( int i = 1;i <= n; i ++)cin >> a[i].first , a[i].second = i ; 
    
    sort(a + 1 , a + n + 1) ; 
    
    for( int i = 1 ; i < n ; i++) insert( i , i + 1 ) , insert( i + 1 , i ) ; //前后左右可移动一格，建立无向图 
    
    for(int i = 1 ; i < n ;  i ++) 
        if(a[i].first == a[i + 1].first) 
             insert(a[i].second , a[i + 1].second) ; //亮度相同正向瞬移建立树 
    
    cout << bfs();
    
    return 0;
}