#include <bits/stdc++.h>
using namespace std;

const int INF = 1e9;


int main() {
    int N;
    cin >> N;
    int A[N];
    int maxA=0;
    for (int i = 0; i < N; ++i) 
    {
        cin >> A[i];
        maxA=max(maxA,A[i]);      
    }
    int dp[N+1][maxA+1];
    
    for (int j = 1; j <= maxA; ++j)
        dp[0][j] = (A[0] == j ? 0 : 1);

    for (int i = 1; i < N; ++i) {
        for (int j = 1; j <= maxA; ++j) {
            dp[i][j] = INF;
            for (int k = 1; k < j; ++k) {
                int cost = (A[i] == j ? 0 : 1);
                dp[i][j] = min(dp[i][j], dp[i - 1][k] + cost);
            }
        }
    }

    
    int res = INF;
    for (int j = 1; j <= maxA; ++j)
        res = min(res, dp[N - 1][j]);

    cout << res << endl;
    return 0;
}