What is the difference between call by value and call by reference in C programming?

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Accepted Answer

Call by value passes a copy of the variable, while call by reference passes the variable's address, allowing direct modification.

Call by Value: A copy of the variable is made. Changes do not affect the original variable.
Example: In a function, if you pass 'x = 5', the function works with a copy of '5'.
Call by Reference: The address of the variable is passed. Changes affect the original variable.
Example: If you pass 'x' directly, modifications in the function will change 'x' itself.
Call by Value is safer as it protects the original data, while Call by Reference is more efficient for large data structures.

Accepted Answer

In call by value, a copy of the argument's value is passed to the function, while in call by reference, the function receives a reference to the actual argument in memory. Changes to the parameter in call by value don't affect the original, whereas in call by reference, modifications persist outside the function.

Accepted Answer

*call by value* : passes a copy of the value, while call by reference passes a reference to the original value. -Call by value creates a new copy of the value being passes. -Call by reference passes a reference to the original value. Changes made to the parameter in call by value do not affect the original value. -Changes made to the parameter in call by reference affect the original value.

Accepted Answer

In Call By Value Or Pass By Value Concept, we pass a copy of the value through actual argument to the formal argument then any changes made in formal argument doesn't reflect to the actual argument.
In Call By Reference Or Pass By Reference Concept, we pass a copy of the value through actual argument to the formal argument then any changes made in formal argument reflects in actual argument.

Accepted Answer

Call by value ----> The function is called by directly passing value of variable as argument.

Call by reference ----> The function is call by directly passing address of variable as argument.

Call by value ----> We need to declare a general variable as function argument.

Call by reference ----> We need to declare a pointer variable as argument.

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What is the difference between call by value and call by reference in C programming?

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