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#include <iostream>
#include <vector>
#include <string>
struct character { int room ; character( int r = 0 ) : room(r) {} };
void pass_by_value( std::vector<character> players )
{ for( character& c : players ) c.room = 99 ; }
void pass_by_reference( std::vector<character>& players )
{ for( character& c : players ) c.room = 99 ; }
std::vector<character> pass_by_value_return_modified_object( std::vector<character> players )
{
for( character& c : players ) c.room = 99 ;
return players ;
}
void print( const std::vector<character>& players )
{
for( character c : players ) std::cout << c.room << ' ' ;
std::cout << '\n' ;
}
int main()
{
{
std::cout << "------ pass by value ------\n" ;
std::vector<character> players { 0, 1, 2, 3, 4, 5 } ;
print(players) ;
pass_by_value(players) ;
print(players) ;
}
{
std::cout << "\n------ pass by reference ------\n" ;
std::vector<character> players { 0, 1, 2, 3, 4, 5 } ;
print(players) ;
pass_by_reference(players) ;
print(players) ;
}
{
std::cout << "\n------ pass by pass by value, return_modified_object------\n" ;
std::vector<character> players { 0, 1, 2, 3, 4, 5 } ;
print(players) ;
std::cout << "ignore the result: " ;
pass_by_value_return_modified_object(players) ; // ignore the result
print(players) ;
std::cout << "update object with the result: " ;
players = pass_by_value_return_modified_object(players) ; // update object with the result
print(players) ;
}
}
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