add first missing positive
add search 2d matrix
add reverse integer
add flaten tree
add remove dup from sorted array
fix typo
add remove duplicates from sorted array ii
add remove dup from linked list
add remove dup from linked list ii
add remove nth form end
add length of last word
add single number ii
add rotate list
add reverse linked list ii
add reverse the nodes in k group
commit changes on the train