回答編集履歴
1
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test
CHANGED
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@@ -6,27 +6,17 @@
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6
6
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public:
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7
7
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Holder(T *p) : val(p) {}
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8
8
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long long Get() const { return static_cast<long long>(*val); }
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9
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-
T*
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9
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+
T *val;
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10
10
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};
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11
11
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12
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class EmptyHolder {
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13
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public:
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14
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EmptyHolder() = default;
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15
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long long Get() const { return -1; }
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16
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};
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17
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-
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18
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-
using TEST =
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19
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-
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12
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+
using TEST = std::variant<Holder<int>, Holder<char>, Holder<long long>>;
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20
13
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21
14
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int main() {
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22
15
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int a = 1;
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23
16
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char b = 'c';
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24
17
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long long c = 10000;
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25
18
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26
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-
TEST test[3];
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27
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-
test[
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19
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+
TEST test[3] = {&a, &b, &c};
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28
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-
test[1] = &b;
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29
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-
test[2] = &c;
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30
20
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for (int i = 0; i < 3; i++) {
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31
21
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std::visit([](auto &v) { std::cout << v.Get() << std::endl; }, test[i]);
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32
22
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}
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