関数の多重定義

C++ Delphi

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関数の多重定義

C++



#include <stdio.h>
int abs(int x)

{

    return (x < 0 ? -x : x);

}

long abs(long x)

{

    return (x < 0L ? -x : x);

}

double abs(double x)

{

    return (x < 0.0 ? -x : x);

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

{
    printf("abs(-6)   = %d\n",  abs(-6));

    printf("abs(-7L)  = %ld\n", abs(-7L));

    printf("abs(-7.9) = %f\n",  abs(-7.9));
    return 0;

}

実行結果



R:\>lesson001\project1.exe

abs(-6)   = 6

abs(-7L)  = 7

abs(-7.9) = 7.900000

Delphi



program Project1;
{$APPTYPE CONSOLE}
uses

    SysUtils;
function abs(x:Longint):Longint; overload;

begin

    if x < 0 then

        result := -x

    else

        result := x;

end;
function abs(x:Real):Real; overload;

begin

    if x < 0 then

        result := -x

    else

        result := x;

end;
procedure main();

begin

    Writeln(Format('abs(-6)   = %d', [abs(-6)]));

    Writeln(Format('abs(-7L)  = %d', [abs(Longint(-7))]));

    Writeln(Format('abs(-7.9) = %f', [abs(-7.9)]));

end;
begin

    main;

end.

実行結果



S:\>lesson001\project1.exe

abs(-6)   = 6

abs(-7L)  = 7

abs(-7.9) = 7.90