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std::map::begin, std::map::cbegin

iterator begin();
 
const_iterator begin() const;
 
const_iterator cbegin() const;
 (since C++11)

Returns an iterator to the first element of the container.

If the container is empty, the returned iterator will be equal to end().

Parameters

(none).

Return value

Iterator to the first element.

Exceptions

(none) (until C++11)
noexcept specification:
noexcept
 (since C++11)

Complexity

Constant.

Example

#include <iostream>
#include <map>
 
int main() {
  std::map<int, float> num_map;
  num_map[4] = 4.13;
  num_map[9] = 9.24;
  num_map[1] = 1.09;
  for (auto it = num_map.begin(); it != num_map.end(); ++it) { // calls a_map.begin() and a_map.end()
    std::cout << it->first << ", " << it->second << '\n';
  }
}

Output:

1, 1.09
4, 4.13
9, 9.24

See also

 returns an iterator to the end
(public member function)

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