How to pass an expression as input and it gives the ceil value as the output?

Question

a. In variables a,b gets the input from the user so as to evaluate the expression from the given input and it gives the ceil and floor values as the output.

 def ceil_flooor():
    a = float(input())
    b = float(input())
    
    print(math.ceil(a))
    print(math.floor(b))

input : 5.5+6.5-8.5 output: 4(ceil value),3(floor value)

I am getting the below error:

"ValueError: could not convert string to float: '5.5+6.5-8.5'"

`float` can only turn a string that looks like a number into a number - it can't evaluate expressions — rdas, Sep 12 '22 at 14:32
use `eval` function on the input, but beware malicious input. — rv.kvetch, Sep 12 '22 at 14:34

score 0 · Accepted Answer · answered Sep 12 '22 at 15:08

0

float() can't evaluate expressions. To achieve what you have in mind, you have to use eval(). This will help evaluate input expressions.

def ceil_flooor():
    a = eval(input())  # <==== edited this line in your code
    b = eval(input())  # <==== edited this line in your code
    
    print(math.ceil(a))
    print(math.floor(b))
    
ceil_flooor()

Input:

5.5 + 1

2.1 + .2

Output:

7

2

answered Sep 12 '22 at 15:08

Chandler Bong

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Obviously with warnings. – Peter Wood Sep 12 '22 at 15:20

How to pass an expression as input and it gives the ceil value as the output?

1 Answers1