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#include <cstdio>
#include <algorithm>

using namespace std;

int main() {
  int n; scanf("%d", &n);
 
  int ones = 0; 
  for (int i=0; i<n; ++i) {
    int x; scanf("%d", &x);
    if (x == 1) {
      ++ones;
    }
  }

  int result = max(0, 2 - ones);

  printf("%d\n", result);
  printf("%d\n", 2);
  printf("%d %d\n", 1, 2);

  return 0;
}