map rbegin() function in C++ STL

C++Server Side ProgrammingProgramming

In this article we will be discussing the working, syntax and examples of map::rbegin() function in C++ STL.

What is a Map in C++ STL?

Maps are the associative container, which facilitates to store the elements formed by a combination of key value and mapped value in a specific order. In a map container the data is internally always sorted with the help of its associated keys. The values in the map container are accessed by its unique keys.

What is a map::rbegin()?

map::rbegin() function is an inbuilt function in C++ STL, which is defined in  header file. rbegin() implies reverse begin function, this function is the reverse of the begin(). This function returns an iterator which is pointing to the last element of the map container.

Syntax

Map_name.rbegin();

Parameter

This function accepts no parameter.

Return value

This function returns the iterator which is pointing to the last element of the map container.

Example

Input

map<char, int> newmap;
newmap[‘a’] = 1;
newmap[‘b’] = 2;
newmap[‘c’] = 3;
newmap.rbegin();

Output

c:3

Example

 Live Demo

#include <bits/stdc++.h>
using namespace std;
int main() {
   map<int, int> TP_Map;
   TP_Map.insert({3, 50});
   TP_Map.insert({2, 30});
   TP_Map.insert({1, 10});
   TP_Map.insert({4, 70});
   //using map::rbegin to fetch first last element
   auto temp = TP_Map.rbegin();
   cout<<"First element is: "<<temp->first << " -> " << temp->second;
   cout<<"\nTP Map is : \n";
   cout << "MAP_KEY\tMAP_ELEMENT\n";
   for (auto i = TP_Map.rbegin(); i!= TP_Map.rend(); i++) {
      cout << i->first << "\t" << i->second << endl;
   }
   return 0;
}

Output

First element is: 4 -> 70
TP Map is:
MAP_KEY    MAP_ELEMENT
4             70
3             50
2             30
1             10
raja
Published on 15-Apr-2020 12:21:42
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