C++ std::map items in descending order of keys

Question

How cal I use std::map container with key value in descending order.

As an example, if insert the following items:

[2 , 5]
[1 , 34]
[3 , 67]
<         


        

Answer 1

Use a custom comparator when the default order doesn't do it for you.
You pass it as the third template parameter ( that's normally defaulted to std::less ).
In your case, you can use std::greater:

std::map > m;

Example code:

#include 

Resulting output:

[1,84]
[0,77]
[-1,42]