#include<iostream>
#include<algorithm>
#include<vector>
using namespace std;
vector < vector <int> > number;
int cmp(int s, int w)
{
return s<w;
}
int main(void)
{
int n, i, j, ans = 0;
cin>>n;
number.resize(2);
number[0].resize(n + 5), number[1].resize(n + 5);
for(i = 0; i<n; i++){
cin>>number[0][i];
number[1][i] = number[0][i];
}
sort(number[1].begin(), number[1].begin() + n, cmp);
for(i = 0; i<n; i++){
for(j = i + 1; j<n; j++){
if(number[0][i] != number[1][i] && number[0][j] != number[1][j] && number[0][i] == number[1][j] && number[1][i] == number[0][j]){
number[0][i] = number[1][i];
number[0][j] = number[1][j];
ans++;
break;
}
}
}
for(i = 0; i<n; i++){
for(j = i + 1; j<n; j++){
if(number[0][i] != number[1][i] && number[0][j] != number[1][j] && number[1][i] == number[0][j]){
number[0][j] = number[0][i];
number[0][i] = number[1][i];
ans++;
break;
}
}
}
cout<<ans;
return 0;
}