def evaluate_expression(expression: str, notation: str) -> float:
"""
Calculates the expression result given its notation.
:param expression: The expression to be calculated
:param notation: The notation type that the expression is written in. I.e. (prefix, infix)
:return: The result of the expression
"""
if notation == PREFIX_NOTATION:
return evaluate_prefix_expression(expression)
if notation == INFIX_NOTATION:
return evaluate_infix_expression(expression)
raise Exception("Invalid notation type")
def test_complex_operations_cases(self):
expression = '- / 10 + 1 1 * 1 2'
result = evaluate_prefix_expression(expression)
assert result == 3
expression = '+ * 2 3 / 4 2'
result = evaluate_prefix_expression(expression)
assert result == 8
expression = '/ * 2 + 3 6 2'
result = evaluate_prefix_expression(expression)
assert result == 9
expression = '* 2 + 2 / 2 2'
result = evaluate_prefix_expression(expression)
assert result == 6
def test_number_only_expression_returns_same_number(self):
expression = '3'
result = evaluate_prefix_expression(expression)
assert result == float(expression)
def test_multiple_subsequent_operators(self):
expression = '+ * 1 2 3'
result = evaluate_prefix_expression(expression)
assert result == 5
def test_multiple_nested_operations_with_numbers_between_operators(self):
expression = '+ 1 * 2 3'
result = evaluate_prefix_expression(expression)
assert result == 7
def test_simple_division(self):
expression = '/ 3 2'
result = evaluate_prefix_expression(expression)
assert result == 1.5
def test_simple_multiplication(self):
expression = '* 2 2'
result = evaluate_prefix_expression(expression)
assert result == 4
def test_simple_subtraction(self):
expression = '- 0 3'
result = evaluate_prefix_expression(expression)
assert result == -3
def test_simple_sum(self):
expression = '+ 2 2'
result = evaluate_prefix_expression(expression)
assert result == 4