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# include <cstdio>


int load_and_count_one_degree_nodes( int nodes_total ) {
  int one_degree_nodes_total = 0;
  for ( int i = 0; i < nodes_total; i ++ ) {
    int current_node_degree;
    scanf( "%d", & current_node_degree );
    if ( current_node_degree == 1 ) {
      one_degree_nodes_total ++;
    }
  }
  return one_degree_nodes_total;
}


void print_solution( int one_degree_nodes_total ) {
  int nodes_to_change;
  if ( one_degree_nodes_total == 0 ) {
    nodes_to_change = 2;
  }
  if ( one_degree_nodes_total == 1 ) {
    nodes_to_change = 1;
  }
  if ( one_degree_nodes_total >= 2 ) {
    nodes_to_change = 0;
  }
  printf( "%d\n", nodes_to_change );
  printf( "2\n" );
  printf( "1 2\n" );
}


int main() {
  int nodes_total;
  scanf( "%d", & nodes_total );
  int one_degree_nodes_total = load_and_count_one_degree_nodes( nodes_total );
  print_solution( one_degree_nodes_total );
  return 0;
}