Base cases
if ( n == 2 ) { return 1 ; } else if ( n == 1 ) { return 0 ; } if ( n % 3 == 0 ) { return 1 + count_minimum_operations ( n / 3 ) ; } else if ( n % 3 == 1 ) { return 1 + count_minimum_operations ( n - 1 ) ; } else { return 1 + count_minimum_operations ( n + 1 ) ; } }