Assign value if not exist in C++

In C++, we can assign a value to a variable only if it does not already have a value assigned to it. This can be done using if-else statements or ternary operators.

Here's an example of using an if-else statement to assign a value if the variable does not already have a value:

``C++ int x;


if (x == 0) {

    x = 10;

}



In this example, we are checking if the variable x has been assigned a value. If x is equal to 0, we assign the value 10 to it.
Here's another example of using a ternary operator to assign a value if the variable does not already have a value:
C++

int y = 0;

y = (y == 0) ? 20 : y;`

This example assigns the value 0 to the variable y. The ternary operator checks if y is equal to 0. If it is, we assign the value 20 to y. If y is not equal to 0, we assign its current value to y`.

It is important to note that assigning a value to an uninitialized variable can result in undefined behavior, so it's always best to initialize variables before using them.

Assign value if not exist in C++

See this concept in other languages