C++ examples for Function:Function Parameter
Using variable-length argument lists.
#include <iostream> #include <iomanip> #include <cstdarg> using namespace std; double average( int, ... ); int main() /*from w w w . j a v a 2 s . co m*/ { double double1 = 37.5; double double2 = 22.5; double double3 = 1.7; double double4 = 10.2; cout << fixed << setprecision( 1 ) << "double1 = " << double1 << "\ndouble2 = " << double2 << "\ndouble3 = " << double3 << "\ndouble4 = " << double4 << endl << setprecision( 3 ) << "\nThe average of double1 and double2 is " << average( 2, double1, double2 ) << "\nThe average of double1, double2, and double3 is " << average( 3, double1, double2, double3 ) << "\nThe average of double1, double2, double3" << " and double4 is " << average( 4, double1, double2, double3, double4 ) << endl; } // calculate average double average( int count, ... ) { double total = 0; va_list list; // for storing information needed by va_start va_start( list, count ); // process variable-length argument list for ( int i = 1; i <= count; i++ ) total += va_arg( list, double ); va_end( list ); // end the va_start return total / count; }