title: Sum Series 23 45 67 89 Upto N Terms
signature: def sumSeries23456789UptoNTerms(n: Int) = {
test_code: import scala.collection.mutable.HashMap
  import scala.collection.immutable.HashSet
  
  
  // SOLUTION CODE
  // ============================================
  PLACEHOLDER_CODE_BODY
  
  
  // TESTING CODE 
  // ============================================
  def validateSolution(actual: Double , expected: Double): Boolean = {
      (actual - expected).abs < 1e-09
  }
  
  def driver(n: Int, expected: Double): String = {
      try {
          if (validateSolution(PLACEHOLDER_FN_NAME(n),expected)) {
              "PASSED"
          } else{
              "FAILED"
          }
      }catch{
          case e: Exception => {e.getClass.getName}
      }
  
  }
  object QuestionEvaluator extends App {
  
      println(s"TEST-0...${driver(
        49, 
        0.7803986631477524    
      )}")   
  
  
      println(s"TEST-1...${driver(
        4, 
        -0.16507936507936516    
      )}")   
  
  
      println(s"TEST-2...${driver(
        60, 
        -0.21050375120783382    
      )}")   
  
  
      println(s"TEST-3...${driver(
        90, 
        -0.21185466678122022    
      )}")   
  
  
      println(s"TEST-4...${driver(
        96, 
        -0.2120245854859959    
      )}")   
  
  
      println(s"TEST-5...${driver(
        29, 
        0.7770671416747363    
      )}")   
  
  
      println(s"TEST-6...${driver(
        86, 
        -0.21172836828074082    
      )}")   
  
  
      println(s"TEST-7...${driver(
        47, 
        0.780190394898247    
      )}")   
  
  
      println(s"TEST-8...${driver(
        77, 
        0.7821931668684383    
      )}")   
  
  
      println(s"TEST-9...${driver(
        87, 
        0.7825573460049735    
      )}")   
  
  }
  
source_py: def sum_series_23_45_67_89_upto_n_terms(n):
      i = 1
      res = 0.0
      sign = True
      while (n > 0):
          n = (n - 1)
          if sign:
              sign = False
              res = (res + ((i + 1) / (i + 2)))
              i = (i + 2)
          else:
              sign = True
              res = (res - ((i + 1) / (i + 2)))
              i = (i + 2)
      return res
source_cpp: double sum_series_23_45_67_89_upto_n_terms(int n) {
    int i = 1;
    double res = 0.0;
    bool sign = true;
    while ( n > 0 ) {
      n --;
      if ( sign ) {
        sign = ! sign;
        res = res + ( double ) ++ i / ++ i;
      }
      else {
        sign = ! sign;
        res = res - ( double ) ++ i / ++ i;
      }
    }
    return res;
  }