Function

A function has the following form:

type name (parameter_1, parameter_2, parameter_...){
	// code to execute inside function
}

For example:

#include <iostream>
using namespace std;

void box(int length, int width, int height); 

int main()//main function
  {
  box(30, 20, 5);//call function "box"

  return 0;
}
//here is function "box"
void box(int length, int width, int height)
  {
  cout << "volume of box is " << length * width * height 
  << "\n";
}

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