32 lines
346 B
C#
32 lines
346 B
C#
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class A {}
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class B : A {}
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class X
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{
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public static A Test (A a, B b)
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{
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return b ?? a;
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}
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public static int Main ()
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{
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A a = new A ();
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B b = new B ();
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if (Test (a, b) != b)
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return 1;
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if (Test (null, b) != b)
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return 2;
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if (Test (a, null) != a)
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return 3;
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if (Test (null, null) != null)
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return 4;
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return 0;
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}
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}
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