> On Dec. 11, 2017, 10 a.m., Andrew Schwartzmeyer wrote: > > Ship It!
Hm, I might take this back. The hypothesis: > In order to count elements a complete traversal of the container is required, while a contains check already has an answer when the first element has been found. While it sounds right, if you check [unordered_map::count](http://en.cppreference.com/w/cpp/container/unordered_map/count) and [unordered_set::count](http://en.cppreference.com/w/cpp/container/unordered_set/count), it does not work like this as these data structures may have at most one matching element. > Returns the number of elements with key that compares equal to the specified > argument key, which is either 1 or 0 since this container does not allow > duplicates. And the stated complexity is: > Constant on average, worst case linear in the size of the container. Which is the same as [find](http://en.cppreference.com/w/cpp/container/unordered_map/count). - Andrew ----------------------------------------------------------- This is an automatically generated e-mail. To reply, visit: https://reviews.apache.org/r/64496/#review193411 ----------------------------------------------------------- On Dec. 11, 2017, 5:31 a.m., Benjamin Bannier wrote: > > ----------------------------------------------------------- > This is an automatically generated e-mail. To reply, visit: > https://reviews.apache.org/r/64496/ > ----------------------------------------------------------- > > (Updated Dec. 11, 2017, 5:31 a.m.) > > > Review request for mesos and Michael Park. > > > Repository: mesos > > > Description > ------- > > In order to check whether a key or value was present in a 'hashset' or > 'hashmap' we were checking whether the count for that entry was > greater than zero. In order to count elements a complete traversal of > the container is required, while a contains check already has an > answer when the first element has been found. > > This patch uses find in contains check for both hashset and hashmap to > avoid the full traversal. > > > Diffs > ----- > > 3rdparty/stout/include/stout/hashmap.hpp > 91085b8d8ad5d35c39c8cc95e3d4765d82d9a8db > 3rdparty/stout/include/stout/hashset.hpp > 6af209c53185207b53396e7687e3bd7357e57bf1 > > > Diff: https://reviews.apache.org/r/64496/diff/1/ > > > Testing > ------- > > `make check` > > > Thanks, > > Benjamin Bannier > >
