The rend() function is an inbuilt function in C++ STL which returns a reverse iterator pointing to the theoretical element right before the first key-value pair in the map(which is considered its reverse end).
Syntax:
map_name.rend()
Parameters:The function does not take any parameter.
Return Value: The function returns a reverse iterator pointing to the theoretical element right before the first element in the map.
Note: Reverse iterators iterate backwards i.e when they are increased they move towards the beginning of the container.
The following programs illustrates the function.
Program 1:
// C++ program to illustrate map::rend() function #include <iostream> #include <map> using namespace std;
int main()
{ map< char , int > mymap;
// Insert pairs in the multimap
mymap.insert(make_pair( 'a' , 1));
mymap.insert(make_pair( 'b' , 3));
mymap.insert(make_pair( 'c' , 5));
// Show content
for ( auto it = mymap.rbegin(); it != mymap.rend(); it++) {
cout << it->first
<< " = "
<< it->second
<< endl;
}
return 0;
} |
c = 5 b = 3 a = 1
Program 2:
// C++ program to illustrate map::rend() function #include <iostream> #include <map> using namespace std;
int main()
{ map< char , int > mymap;
// Insert pairs in the multimap
mymap.insert(make_pair( 'a' , 1));
mymap.insert(make_pair( 'b' , 3));
mymap.insert(make_pair( 'c' , 5));
// Get the iterator pointing to
// the preceding position of
// 1st element of the map
auto it = mymap.rend();
// Get the iterator pointing to
// the 1st element of the multimap
it--;
cout << it->first
<< " = "
<< it->second;
return 0;
} |
a = 1