title: Sum Series 23 45 67 89 Upto N Terms
signature: sumSeries23456789UptoNTerms :: Integer -> Double
  sumSeries23456789UptoNTerms n = 
test_code: import Text.Printf
  import Control.Exception (catch, SomeException)
  import Data.Typeable
  import qualified Data.List as List
  import qualified Data.Map as Map
  import qualified Data.Set as Set
  
  -- SOLUTION CODE
  -- ============================================
  
  PLACEHOLDER_CODE_BODY
  
  -- TESTING CODE 
  -- ============================================
  validateSolution :: Double -> Double -> Bool
  validateSolution actual expected = do
      (abs (actual-expected)) < 1e-09
  
  driver :: Integer -> Double -> String
  driver n expected = do
      if (validateSolution (PLACEHOLDER_FN_NAME n) expected)
          then "PASSED"
      else "FAILED"
  
  main = do
      printf "TEST-0...%s\n" (driver (49) (0.7803986631477524) )
  
      printf "TEST-1...%s\n" (driver (4) (-0.16507936507936516) )
  
      printf "TEST-2...%s\n" (driver (60) (-0.21050375120783382) )
  
      printf "TEST-3...%s\n" (driver (90) (-0.21185466678122022) )
  
      printf "TEST-4...%s\n" (driver (96) (-0.2120245854859959) )
  
      printf "TEST-5...%s\n" (driver (29) (0.7770671416747363) )
  
      printf "TEST-6...%s\n" (driver (86) (-0.21172836828074082) )
  
      printf "TEST-7...%s\n" (driver (47) (0.780190394898247) )
  
      printf "TEST-8...%s\n" (driver (77) (0.7821931668684383) )
  
      printf "TEST-9...%s\n" (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;
  }