Difference between arguments and parameters in C/C++

Argument

An argument refers to the values ​​passed into a function when the function is called. These values ​​are usually the source of the function that requests arguments during execution. These values ​​are assigned to variables in the definition of the called function. The types of the values ​​passed into the function are the same as the types of the variables defined in the function definition. They are also called actual arguments or actual parameters.

For example, suppose we need to call a function sum() with two numbers to add. These two numbers are called arguments and are passed to sum() when it is called from somewhere else.

C

// C code to illustrate Arguments #include // sum: Function definition int sum(int a, int b) { // returning the addition return a + b; } // Driver code int main() { int num1 = 10, num2 = 20, res; // sum() is called with // num1 & num2 as ARGUMENTS. res = sum(num1, num2); // Displaying the result printf("The summation is %d", res); return 0; }

C++

// C++ code to illustrate Arguments #include using namespace std; // sum: Function definition int sum(int a, int b) { // returning the addition return a + b; } // Driver code int main() { int num1 = 10, num2 = 20, res; // sum() is called with // num1 & num2 as ARGUMENTS. res = sum(num1, num2); // Displaying the result cout << "The summation is " << res; return 0; }

Output:

The summation is 30

Parameters

Parameters are variables defined in a function declaration or function definition. These variables are used to receive arguments passed during a function call. Parameters in a function prototype are applied to the execution of the function in which it is defined. They are also called formal arguments or formal parameters.

For example, suppose we need to define a Mult() function to multiply two numbers. These two numbers are considered as parameters and are defined while defining the Mult() function.

C

// C code to illustrate Parameters #include // Mult: Function definition // a and b are the PARAMETERS int Mult(int a, int b) { // returning the multiplication return a * b; } // Driver code int main() { int num1 = 10, num2 = 20, res; // Mult() is called with // num1 & num2 as ARGUMENTS. res = Mult(num1, num2); // Displaying the result printf("The multiplication is %d", res); return 0; }

C++

// C++ code to illustrate Parameters #include using namespace std; // Mult: Function definition // a and b are the parameters int Mult(int a, int b) { // returning the multiplication return a * b; } // Driver code int main() { int num1 = 10, num2 = 20, res; // Mult() is called with // num1 & num2 as ARGUMENTS. res = Mult(num1, num2); // Displaying the result cout << "The multiplication is " << res; return 0; }

Output:

The multiplication is 200

Difference between Argument and Parameter

int num = 20; Call(num) // num is argument

int Call(int rnum) { printf("the num is %d", rnum); } // rnum is parameter

Samuel Daniel

Update 16 December 2024