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      std::vector<T,Allocator>::size

      From cppreference.com
      <cpp‎ |container‎ |vector

      [edit template]
       
       
       
      std::vector
      Member types
      Member functions
      Non-member functions
      (until C++20)(until C++20)(until C++20)(until C++20)(until C++20)
      Deduction guides(C++17)
       
      size_type size()const;
      		(noexcept since C++11)
      (constexpr since C++20)

      Returns the number of elements in the container.

      Contents

      [edit]Return value

      std::distance(begin(), end())

      [edit]Complexity

      Constant.

      [edit]Example

      [edit]

      The following code usessize to display the number of elements in astd::vector<int>:

      Run this code
      #include <cassert>#include <vector> int main(){std::vector<int> nums;assert(nums.size()==0);    nums={1,2,3,4};assert(nums.size()==4);}

      [edit]See also

      returns the number of elements that can be held in currently allocated storage
      (public member function)[edit]
      checks whether the container is empty
      (public member function)[edit]
      returns the maximum possible number of elements
      (public member function)[edit]
      changes the number of elements stored
      (public member function)[edit]
      (C++17)(C++20)
      		 returns the size of a container or array
      (function template)[edit]
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