import sys,io,os
try:Z=io.BytesIO(os.read(0,os.fstat(0).st_size)).readline
except:Z=lambda:sys.stdin.readline().encode()
Y=lambda:map(sub,Z().split())
sub=lambda x:int(x)-1
n=int(Z());a=[*Y()];L=[-1]*n
for i in range(n):L[a[i]]=i
for x in range(n):
if x!=L[a[x]]:break
s={a[x]};ns=set();r=0
for i in range(x+1,n):
if s:
if i==L[a[i]]:
if a[i]in ns:ns.remove(a[i])
elif a[i]in s:
s.remove(a[i])
if not s:s,ns=ns,set();r-=1
elif a[i]not in s:ns.add(a[i])
r+=1
elif i!=L[a[i]]:s.add(a[i])
print(r)#include <algorithm>
#include <deque>
#include <iostream>
#include <map>
#include <queue>
#include <set>
#include <string>
#include <unordered_map>
#include <vector>
using namespace std;
typedef long long ll;
typedef vector<int> veci;
typedef vector<ll> vecll;
long long mod = 998244353;
int main(){
int n;
cin >> n;
vector<int> a(n, 0);
for(auto& x : a) cin >> x;
map<int, int> l, r;
for(int i = n - 1; i >= 0; --i){
if(r.find(a[i]) == r.end()) r[a[i]] = i;
}
int m = 0, begin = 0, end, pivot = 1;
while(begin < n){
//cerr << "begin : " << begin <<endl;
end = r[a[begin]];
++m;
//cerr << "increment " << m << endl;
pivot = max(pivot, begin + 1);
int new_begin = -1, new_end = -1;
while(pivot < end){
if(r[a[pivot]] > end){
if(r[a[pivot]] > new_end){
new_end = r[a[pivot]];
new_begin = pivot;
}
}
++pivot;
}
if(new_begin == -1){
//cerr << "next chunk" << endl;
if(end > begin) ++m;
//cerr << "increment " << m << endl;
begin = end + 1;
}
else{
begin = new_begin;
}
}
cout << n - m << endl;
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