sevaseva
sevaseva
/ custom_eval_string_numeric_expression.py
Last active
October 28, 2018 06:58
custom eval function in python for a nonempty sting that may contain only '0'..'9', '+', '*'
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| ORD_OF_ZERO = ord('0') | |
| def _eval(str): | |
| ''' Returns an integer, a result of evaluation of a nonempty str | |
| that may contain only '0'..'9', '+', '*'. | |
| Summary of the algorithm: | |
| * .split('+') the string into products (strings), | |
| * then .split('*') each product string into numbers (strings), | |
| * evaluate each number (string) into an integer, | |
| * multiply all numbers within each product to get the numerical product, |