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Merge pull request #2119 from Jaskamalkainth/master
[C++ / en] Added Tuple.
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@ -955,6 +955,52 @@ v.push_back(Foo()); // New value is copied into the first Foo we inserted
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// explanation of why this works.
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v.swap(vector<Foo>());
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///////////////////////////////////////
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// Tuples (C++11 and above)
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///////////////////////////////////////
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#include<tuple>
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// Conceptually, Tuples are similar to old data structures (C-like structs) but instead of having named data members ,
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// its elements are accessed by their order in the tuple.
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// We start with constructing a tuple.
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// Packing values into tuple
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auto first = make_tuple(10,'A');
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const int maxN = 1e9;
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const int maxL = 15;
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auto second = make_tuple(maxN,maxL);
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// printing elements of 'first' tuple
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cout << get<0>(first) << " " << get<1>(first) << "\n"; //prints : 10 A
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// printing elements of 'second' tuple
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cout << get<0>(second) << " " << get<1>(second) << "\n"; // prints: 1000000000 15
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// Unpacking tuple into variables
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int first_int;
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char first_char;
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tie(first_int,first_char) = first;
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cout << first_int << " " << first_char << "\n"; // prints : 10 A
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// We can also create tuple like this.
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tuple<int,char,double> third (11,'A',3.14141);
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// tuple_size returns number of elements in a tuple (as a constexpr)
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cout << tuple_size < decltype(third) >::value << "\n"; // prints: 3
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// tuple_cat concatenates the elements of all the tuples in the same order.
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auto concatenated_tuple = tuple_cat( first, second ,third);
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// concatenated_tuple becomes = (10,'A',1e9,15,11,'A',3.14141)
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cout << get<0>(concatenated_tuple) << "\n"; // prints: 10
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cout << get<3>(concatenated_tuple) << "\n"; // prints: 15
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cout << get<5>(concatenated_tuple) << "\n"; // prints: 'A'
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```
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Further Reading:
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