input: Write a python function to find the minimum length of a contiguous subarray whose sum is at least a given value.
  assert checkContiguousSubarray([1, 4, 20, 3, 10, 5], 33) == 3
  assert checkContiguousSubarray([1, 2, 3, 4, 5], 11) == 3
  assert checkContiguousSubarray([1, 2, 3, 4, 5], 15) == 5
  assert checkContiguousSubarray([1, 2, 3, 4, 5], 16) == "Not Possible"
output: def checkContiguousSubarray(arr, target):
      n = len(arr)
      min_length = float('inf')
      left = 0
      current_sum = 0
      
      for right in range(n):
          current_sum += arr[right]
          
          while current_sum >= target:
              min_length = min(min_length, right - left + 1)
              current_sum -= arr[left]
              left += 1
              
      return min_length if min_length != float('inf') else "Not Possible"