





from __future__ import annotations




def     __UpperCamelCase						(_SCREAMING_SNAKE_CASE	,		_SCREAMING_SNAKE_CASE	,		_SCREAMING_SNAKE_CASE	,		)       ->     Any:






  if (electron_conc, hole_conc, intrinsic_conc).count(0	) != 1:
    raise ValueError('You cannot supply more or less than 2 values'	)
  elif electron_conc < 0:
    raise ValueError('Electron concentration cannot be negative in a semiconductor'	)
  elif hole_conc < 0:
    raise ValueError('Hole concentration cannot be negative in a semiconductor'	)
  elif intrinsic_conc < 0:
    raise ValueError(
        'Intrinsic concentration cannot be negative in a semiconductor'	)
  elif electron_conc == 0:
    return (
        "electron_conc",
        intrinsic_conc**2 / hole_conc,
    )
  elif hole_conc == 0:
    return (
        "hole_conc",
        intrinsic_conc**2 / electron_conc,
    )
  elif intrinsic_conc == 0:
    return (
        "intrinsic_conc",
        (electron_conc * hole_conc) ** 0.5,
    )
  else:
    return (-1, -1)


if __name__ == "__main__":
      import doctest

      doctest.testmod()









def     __UpperCamelCase						(_SCREAMING_SNAKE_CASE = 50	)       ->     int:
  lowercase__			    =						[1] * (length + 1)

  for row_length in range(3	,		length + 1	):
    for block_length in range(3	,		row_length + 1	):
      for block_start in range(row_length - block_length	):
        ways_number[row_length] += ways_number[
            row_length - block_start - block_length - 1
        ]

      ways_number[row_length] += 1

  return ways_number[length]


if __name__ == "__main__":
      print(f'''{solution() = }''')


