040000 tree 14a5cc881b87a694c50d44c1cee77db3abb1edc0	alg.merge
040000 tree 7d420c1ee82620a7c1acde95a3adc7b653388f1f	alg.modifying.operations
040000 tree 7c640f83595beeafe429a7afcdab36bd3fc86e4c	alg.nonmodifying
040000 tree 67c4e8a3892a64b17bba2db682c17cd6a9f0f347	alg.sorting