Function Overloading

[anonymous156]

How can I create two functions that has the same name GetAve. The first function should have 3 parameters for whole numbers and the second one should have 3 parameters for numbers with decimal points.

#include <iostream>
using namespace std;

int main()
{
	GetAve(20, 60, 100);
	GetAve(2.41, 3.333, 12.25);

	int x,y,z;
	cout<<"x = "; cin>>x;
	cout<<"y = "; cin>>y;
	cout<<"z = "; cin>>z;
	GetAve(x,y,z);
	
	float a,b,c;
	cout<<"a = "; cin>>a;
	cout<<"b = "; cin>>b;
	cout<<"c = "; cin>>c;
	GetAve(a,b,c);
	
	double u,v,w;
	cout<<"u = "; cin>>u;
	cout<<"v = "; cin>>v;
	cout<<"w = "; cin>>w;
	GetAve(u,v,w);
	
	return 0;
}

Sample output:

Average of 20, 60, and 100 is 60

Average of 2.41, 3.333, ad 12.25 is 5.99767

x = 2
y = 6
z = 9
Average of 2, 6, and 9, is 5

a = 2
b = 6
c = 9
Average of 2, 6, and 9 is 5.66667

u = 1.2
v = 2.4
w = 3.6
Average of 1.2, 2.4, and 3.6 is 2.4 

[George P]

https://www.programiz.com/cpp-programming/function-overloading

[anonymous156]

How to make the function with 3 parameters? I still can't understand it

[thmm]

No need to create 2 functions.

#include <iostream>

//requires c++20
auto GetAverage(auto a, auto b, auto c)
{
  return (a + b + c) / 3;
}


int main()
{
  std::cout << "Average of 20, 60 and 100 is: " << GetAverage(20, 60, 100)<< "\n";
  std::cout << "Average of 2.41, 3.333, ad 12.25 is: " << GetAverage(2.41, 3.333, 12.25);
}

[anonymous156]

So this is my code but the output that i get is wrong.

#include <iostream>
using namespace std;

void GetAve (int ave1, int ave2, int ave3)
{
	int average;
	average = ((ave1, ave2, ave3)/3);
	
	cout << "Average of " << ave1 << ", " << ave2 << ", and " << ave3 << " is " << average << "\n" << endl;
}
void GetAve (double ave1, float ave2, double ave3)
{
	float average;
	average = ((ave1, ave2, ave3)/3);
	
	cout << "Average of " << ave1 << ", " << ave2 << ", and " << ave3 << " is " << average << "\n" << endl;
}
int main()
{
	GetAve(20, 60, 100);
	GetAve(2.41, 3.333, 12.25);

	int x,y,z;
	cout<<"x = "; cin>>x;
	cout<<"y = "; cin>>y;
	cout<<"z = "; cin>>z;
	GetAve(x,y,z);
	
	float a,b,c;
	cout<<"a = "; cin>>a;
	cout<<"b = "; cin>>b;
	cout<<"c = "; cin>>c;
	GetAve(a,b,c);
	
	double u,v,w;
	cout<<"u = "; cin>>u;
	cout<<"v = "; cin>>v;
	cout<<"w = "; cin>>w;
	GetAve(u,v,w);
	
	return 0;
}

output:

Average of 20, 60, and 100 is 33

Average of 2.41, 3.333, and 12.25 is 4.08333

x = 2
y = 6
z = 9
Average of 2, 6, and 9 is 3

[anonymous156]

20, 60, and 100 should be 60

2, 6, and 9 should be 5.66667

[anonymous156]

@thmm it should be two functions and the main function should be like this:

int main()
{
	GetAve(20, 60, 100);
	GetAve(2.41, 3.333, 12.25);

	int x,y,z;
	cout<<"x = "; cin>>x;
	cout<<"y = "; cin>>y;
	cout<<"z = "; cin>>z;
	GetAve(x,y,z);
	
	float a,b,c;
	cout<<"a = "; cin>>a;
	cout<<"b = "; cin>>b;
	cout<<"c = "; cin>>c;
	GetAve(a,b,c);
	
	double u,v,w;
	cout<<"u = "; cin>>u;
	cout<<"v = "; cin>>v;
	cout<<"w = "; cin>>w;
	GetAve(u,v,w);
	
	return 0;
}

or else it will not get accepted.

[Peter87]

The comma operator is a binary operator that first evaluates the first operand and discards the result, then it evaluates the second operand and uses that as the result of the expression.

That means

average = (ave1, ave2, ave3)/3;

has the same meaning as

average = ave3/3;

[lastchance]

Your model answer (first cin input case) is a bit dubious.

You will also have a few ambiguity problems if the input variables are any type of whole number other than an int (long or long long or unsigned, for example). (As would the following code). This isn't a great function to be overloading.

#include <iostream>
using namespace std;

void GetAve (double ave1, double ave2, double ave3)
{
	double average = ( ave1 + ave2 + ave3 ) / 3.0;
	cout << "Average of " << ave1 << ", " << ave2 << ", and " << ave3 << " is " << average << "\n\n";
}

void GetAve (int ave1, int ave2, int ave3)
{
	GetAve( double(ave1), double(ave2), double(ave3) );
}

int main()
{
	GetAve(20, 60, 100);
	GetAve(2.41, 3.333, 12.25);

	int x,y,z;
	cout<<"x = "; cin>>x;
	cout<<"y = "; cin>>y;
	cout<<"z = "; cin>>z;
	GetAve(x,y,z);
	
	float a,b,c;
	cout<<"a = "; cin>>a;
	cout<<"b = "; cin>>b;
	cout<<"c = "; cin>>c;
	GetAve(a,b,c);
	
	double u,v,w;
	cout<<"u = "; cin>>u;
	cout<<"v = "; cin>>v;
	cout<<"w = "; cin>>w;
	GetAve(u,v,w);
}

[seeplus]

It looks like the requirement for the whole number version is for a whole number answer and of that for the decimal point version is for a decimal point answer. In that case, the result for the whole number version could be misleading. But if that is what is wanted...

#include <iostream>
using namespace std;

void GetAve(int a, int b, int c) {
	cout << "\nAverage of " << a << ", " << b << " and " << c << " is " << (a + b + c) / 3 << '\n';
}

void GetAve(double a, double b, double c) {
	cout << "\nAverage of " << a << ", " << b << " and " << c << " is " << (a + b + c) / 3.0 << '\n';
}

int main() {
	GetAve(20, 60, 100);
	GetAve(2.41, 3.333, 12.25);

	int x, y, z;
	cout << "x = "; cin >> x;
	cout << "y = "; cin >> y;
	cout << "z = "; cin >> z;
	GetAve(x, y, z);

	float a, b, c;
	cout << "a = "; cin >> a;
	cout << "b = "; cin >> b;
	cout << "c = "; cin >> c;
	GetAve(a, b, c);

	double u, v, w;
	cout << "u = "; cin >> u;
	cout << "v = "; cin >> v;
	cout << "w = "; cin >> w;
	GetAve(u, v, w);
}

Average of 20, 60 and 100 is 60

Average of 2.41, 3.333 and 12.25 is 5.99767
x = 2
y = 6
z = 9

Average of 2, 6 and 9 is 5
a = 2
b = 6
c = 9

Average of 2, 6 and 9 is 5.66667
u = 1.2
v = 2.4
w = 3.6

Average of 1.2, 2.4 and 3.6 is 2.4

[JLBorges]

#include <iostream>
#include <concepts> // https://en.cppreference.com/w/cpp/concepts

// average of three integer values
double average( std::integral auto a, std::integral auto b, std::integral auto c )
{
    return ( double(a) + b + c ) / 3 ; // avoid integer division and potential integer overflow
}

// average of three floating point values
double average( std::floating_point auto a, std::floating_point auto b, std::floating_point auto c )
{
    return (a+b+c) / 3 ;
}

// average of three numbers, where some are integers and others are floating point
template < typename T > concept number = std::integral<T> || std::floating_point<T> ;

double average( number auto a, number auto b, number auto c ) // less specialised than the two earlier functions
{
    return (a+b+c) / 3 ;
}

int main()
{
    std::cout << average( 1, 2ULL, char(52) ) << '\n' // 18.3333 (three integer values)
              << average( 1.2, 3.4f, 4.5L ) << '\n' // 3.0333 (three floating point values)
              << average( 1, 3.4, 5 ) << '\n' ; // 3.1333 (mixed integer and floating point values)

    // average( nullptr, "abcd", 8 ) ; // *** error *** : no matching function (constraints not satisfied)
}

http://coliru.stacked-crooked.com/a/61b021e5bb75092d