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#include <cstdio>

int main(int argc, char** argv) {
  int n, ones, a, res;
  scanf("%d",&n);
  ones = 0;
  for(int i=0;i<n;i++) {
    scanf("%d", &a);
    if(a == 1) {
      ones++;
    }
  }
  res = 0;
  if(ones < 2) {
    res = 2 - ones;
  }
  printf("%d\n", res);
  printf("2\n");
  printf("1 2\n");
  return 0;
}