dddddddddd

#include <iostream>
#include <algorithm>
#include <vector>
using namespace std;

int main() {
    int n, cnt=0;
    cin >> n;
    vector <int> a(n);
    for (int i = 0; i<n; i++) {
        cin >> a[i];
    }
    for (int i = 1; i<n-1; i++) {
        if (a[i-1]==a[i] and a[i]==a[i+1]) {
            cnt+=3;
            for (int j=i+2; j<n-1; j++) {
                if (a[j]==a[i+1]) {
                    cnt++;
                } else break;
            }
        }
    } cout << cnt;
}