do while

There are two possibilities to loop over a block:

        flowchart TD
_s(start) --> a
    a[.] --> b{?}
    b -->|false| a
    b -->|true| _e
_e(end)
    

        flowchart TD
_s(start) --> b{?}
    b -->|false| a[.]
    a --> b
    b -->|true| _e

_e(end)
    

🤔 Question to ponder

You want to integrate an email input field with input validation in your program, e.g., there must be an @ in the input string. Which one fits better ?

        flowchart TD
_s(start) --> a
    a[read input] --> b{input valid?}
    b -->|false| a
    b -->|true| c[process input]  --> _e

_e(end)
    

        flowchart TD
_s(start) --> b{input valid?}
    b -->|false| a[read input]
    a --> b
    b -->|true| c[process input]  --> _e

_e(end)
    

Activity 28 (User input)

Implement a program that exits if the string ‘exit’ is read.