there is no check for valid / number of inputs in the calculator
steps to reproduce : put double closing brackets or multiple operators together or multiple decimals
expected result - an error message for invalid input
actual result - the alculator makes an attempt to alculate and gives NaN as output
there is no check for valid / number of inputs in the calculator steps to reproduce : put double closing brackets or multiple operators together or multiple decimals expected result - an error message for invalid input actual result - the alculator makes an attempt to alculate and gives NaN as output