Analysis and introduction to the difference between input() and raw_input() in python

Let’s look at the source code of input

def input(prompt):
return eval(raw_input(prompt))

In fact, input also calls raw_input, just do Eval processing

And what is the role of eval?

input: Type conversion will be done based on the user's input
raw_input: The user's input will be processed as a string

The following is a detailed supplement :

First of all, we know that input() and raw_input() are used to obtain input from the console. Of course, you can add input prompt information when inputting:

        a = raw_input("Please input a:")
        b = input("Please input b:")

Then What's the difference between the two?

Input() supports users to input numbers or expressions, but does not support input of strings. It returns a numerical value of numeric type. Raw_input() captures the original input, which means it returns a string, so if the input is a number, then we must perform a forced conversion. For example:

   a = int(raw_input("Please input the number a:"))

In fact, input() is essentially implemented using raw_input(). It just calls the eval() function after calling raw_input(). Therefore, unless there is a special need for input(), otherwise Under normal circumstances, we recommend using raw_input() to interact with users.

map receives a function and an iterable object (such as a list) as parameters, processes each element with the function, and then returns a new list.
ACM sometimes needs to input a line format such as a b c. In this case, it uses the map function to process it. It is assumed that a, b, and c are all integers.
a,b,c = map(int, raw_input().split()), the raw_input function input is a string, and the split method of the string is used to split the string into sequences.

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