73 lines
738 B
C#
73 lines
738 B
C#
using System;
|
|
|
|
struct S1
|
|
{
|
|
public static implicit operator int (S1? s)
|
|
{
|
|
return 1;
|
|
}
|
|
}
|
|
|
|
struct S2
|
|
{
|
|
public static implicit operator int? (S2? s)
|
|
{
|
|
return null;
|
|
}
|
|
}
|
|
|
|
struct S3
|
|
{
|
|
public static implicit operator int? (S3? s)
|
|
{
|
|
return 2;
|
|
}
|
|
}
|
|
|
|
struct S4
|
|
{
|
|
public static implicit operator int? (S4 s)
|
|
{
|
|
return 3;
|
|
}
|
|
}
|
|
|
|
class C
|
|
{
|
|
public static int Main ()
|
|
{
|
|
S1? s1 = new S1 ();
|
|
switch (s1) {
|
|
case 1:
|
|
break;
|
|
default:
|
|
return 1;
|
|
}
|
|
|
|
S2? s2 = new S2 ();
|
|
switch (s2) {
|
|
case null:
|
|
break;
|
|
default:
|
|
return 2;
|
|
}
|
|
|
|
S3? s3 = new S3 ();
|
|
switch (s3) {
|
|
case 2:
|
|
break;
|
|
default:
|
|
return 3;
|
|
}
|
|
|
|
S4 s4 = new S4 ();
|
|
switch (s4) {
|
|
case 3:
|
|
break;
|
|
default:
|
|
return 4;
|
|
}
|
|
|
|
return 0;
|
|
}
|
|
} |