D

#include <algorithm>
#include <cassert>
#include <cstdio>
#include <iostream>
#include <set>
#include <vector>

using namespace std;

const int N = 1000000;
const int oo = N + 1;

int n;
int a[N];
int d[N][3];


int main() {
  cin >> n;
  assert(1 <= n && n <= N);
  for (int i = 0; i < n; i++) {
    cin >> a[i];
    assert(a[i] == -1 || a[i] == 0 || a[i] == 1);
    a[i] += 1;
  }
  for (int i = 0; i < n; i++) {
    for (int j = 0; j < 3; j++) {
      d[i][j] = oo;
    }
  }

  d[0][a[0]] = 0;

  for (int i = 1; i < n; i++) {
    for (int j = 0; j < 3; j++) if (j <= a[i]) {
      d[i][a[i]] = min(d[i][a[i]], d[i-1][j]);
    }
    for (int j = 0; j < 3; j++) {
      for (int c = 1; c <= 2; c++) {
        int k = c * (j - 1) + a[i];
        if (k >= 0 && k < 3 && j <= k) {
          d[i][k] = min(d[i][k], d[i-1][j] + c);
        }
      }
    }
  }

  int r = oo;
  for (int j = 0; j < 3; j++) {
    r = min(r, d[n - 1][j]);
  }
  if (r == oo) {
    cout << "Mumkun emes" << endl;
  } else {
    cout << r << endl;
  }
  return 0;
}