equal_range « STL Algorithms Binary search « C++ Tutorial

26.2.1.Use equal_range to determine both the lower- and upper-bound insertion points
26.2.2.equal_range and distance
26.2.3.Use equal function to check whether both collections are equal
26.2.4.Use equal function to check for corresponding even and odd elements
26.2.5.Use equal_range to locate the first and last point at which 5 can be inserted in order
26.2.6.equal_range( v.begin(), v.end(), 6 )