title: Sum Series 23 45 67 89 Upto N Terms
signature: def sum_series_23_45_67_89_upto_n_terms(n):
test_code: import array
  import bisect
  import collections
  import datetime
  import functools
  import heapq
  import itertools
  import math
  import queue
  import re
  import string
  import sys
  from typing import Any, Dict, List, Optional, Set
  
  
  # SOLUTION CODE
  # ============================================
  PLACEHOLDER_CODE_BODY
  
  # TESTING CODE 
  # ============================================
  def validate_solution(actual, expected):
      return abs(actual - expected) < 1e-09
  
  def driver(n, expected):
      try:
          if validate_solution(PLACEHOLDER_FN_NAME(
              n),
              expected
          ):
              return "PASSED"
          return "FAILED"
      except Exception as exception_obj:
          return type(exception_obj).__name__
      
  if __name__ == "__main__":
      result = driver(49, 0.7803986631477524)
      print(f"TEST-0...{result}")
  
      result = driver(4, -0.16507936507936516)
      print(f"TEST-1...{result}")
  
      result = driver(60, -0.21050375120783382)
      print(f"TEST-2...{result}")
  
      result = driver(90, -0.21185466678122022)
      print(f"TEST-3...{result}")
  
      result = driver(96, -0.2120245854859959)
      print(f"TEST-4...{result}")
  
      result = driver(29, 0.7770671416747363)
      print(f"TEST-5...{result}")
  
      result = driver(86, -0.21172836828074082)
      print(f"TEST-6...{result}")
  
      result = driver(47, 0.780190394898247)
      print(f"TEST-7...{result}")
  
      result = driver(77, 0.7821931668684383)
      print(f"TEST-8...{result}")
  
      result = driver(87, 0.7825573460049735)
      print(f"TEST-9...{result}")
  
      sys.exit(0)
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;
  }