#include <bits/stdc++.h>
using namespace std;
struct segment {
  int st, ed;
} lb[10100];
int dp[10100];
char str[10100];
int main() {
  int n;
  scanf("%d%*c", &n);
  gets(str);
  int i, j, p = 1;
  for (i = 0; str[i]; i++) {
    while (str[i] == ' ') i++;
    lb[p].st = i;
    while (isalpha(str[i]) || str[i] == ' ') i++;
    lb[p].ed = i;
    if (lb[p].ed - lb[p].st + 1 > n) {
      printf("Impossible\n");
      return 0;
    }
    p++;
  }
  dp[0] = 0;
  dp[1] = 1;
  for (i = 2; i < p; i++) {
    dp[i] = dp[i - 1] + 1;
    for (j = i - 1; j >= 1; j--) {
      if (lb[i].ed - lb[j].st < n)
        dp[i] = dp[j - 1] + 1;
      else
        break;
    }
  }
  printf("%d\n", dp[p - 1]);
  return 0;
}
