How to find an element in a specified range in std::map?

You can use std::lower_bound, std::upper_bound or std::equal_range for that as std::map iterators and data in the map satisfy the requirement for those functions, though you should be aware that it will be less efficient than std::map::find() due to linear iterator increments.

From std::lower_bound documentation

The number of comparisons performed is logarithmic in the distance between first and last (At most log 2(last - first) + O(1) comparisons). However, for non-LegacyRandomAccessIterators, the number of iterator increments is linear.

emphasis is mine.