title: Count Possible Ways To Construct Buildings
signature: count_possible_ways_to_construct_buildings <- function(n) {
test_code: 
  
  
  # SOLUTION CODE
  # ============================================
  PLACEHOLDER_CODE_BODY
  
  # TESTING CODE 
  # ============================================
  validate_solution <- function(actual, expected) {
      toString(actual)==toString(expected)
  }
  
  driver <- function(n, expected){
      if (validate_solution(PLACEHOLDER_FN_NAME(n), expected)){
          "PASSED"
      } else{
          "FAILED"
      }
  }
  
  main <- function() {
      cat(sprintf("TEST-0...%s\n",driver(
          17L, 
          17480761L
      )))
  
      cat(sprintf("TEST-1...%s\n",driver(
          34L, 
          222915410843904L
      )))
  
      cat(sprintf("TEST-2...%s\n",driver(
          9L, 
          7921L
      )))
  
  }
  
  main()
source_py: def count_possible_ways_to_construct_buildings(N):
      if (N == 1):
          return 4
      countB = 1
      countS = 1
      for i in range(2, (N + 1)):
          prev_countB = countB
          prev_countS = countS
          countS = (prev_countB + prev_countS)
          countB = prev_countS
      result = (countS + countB)
      return (result * result)
source_cpp: int count_possible_ways_to_construct_buildings(int N) {
    if ( N == 1 ) return 4;
    int countB = 1, countS = 1, prev_countB, prev_countS;
    for ( int i = 2;
    i <= N;
    i ++ ) {
      prev_countB = countB;
      prev_countS = countS;
      countS = prev_countB + prev_countS;
      countB = prev_countS;
    }
    int result = countS + countB;
    return ( result * result );
  }