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).
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.
c = 5 b = 3 a = 1
a = 1