構造体とメンバの透過性

C++ Delphi

Cプログラマのための C++入門 > 2.クラスの概念 >

構造体とメンバの透過性

C++



#include <stdio.h>
struct student

{

    char    name[20];

    int     eng;

    int     math;

    int     ave;

};
void calc_ave(student* x)

{

    x->ave = (x->eng + x->math) / 2;

}
int average(student* x)

{

    return x->ave;

}
int main(int argc, char* argv[])

{

    student x;
    x.eng  = 60;

    x.math = 70;
    calc_ave(&x);
    printf("eng  = %d\n",  x.eng);

    printf("math = %d\n",  x.math);

    printf("ave  = %d\n",  average(&x));
    return 0;

}

実行結果



R:\>lesson002\project1.exe

eng  = 60

math = 70

ave  = 65

Delphi



program Project1;
{$APPTYPE CONSOLE}
uses

    SysUtils;
type

    TStudent =  record

        eng:    Integer;

        math:   Integer;

        ave:    Integer;

end;



procedure calc_ave(var x:TStudent);

begin

    x.ave := (x.eng + x.math) div 2;

end;
function average(x:TStudent):Integer;

begin

    result := x.ave;

end;
procedure main();

var

    x:  TStudent;

begin

    x.eng  := 60;

    x.math := 70;
    calc_ave(x);
    Writeln(Format('eng  = %d', [x.eng]));

    Writeln(Format('math = %d', [x.math]));

    Writeln(Format('ave  = %d', [average(x)]));

end;
begin

    main;

end.

実行結果



S:\>lesson002\project1.exe

eng  = 60

math = 70

ave  = 65