Day 16 | 104.MaximumDepth of BinaryTree| 111.MinimumDepth of BinaryTree| 222.CountComplete TreeNodes
Day1|704.BinarySearch|27.RemoveElement|35.SearchInsertPosition|34.FirstandLastPositionofElementinSortedArrayDay2|977.SquaresofaSortedArray|209.MinimumSizeSubarraySum|59.SpiralMatrixIIDay3|203.RemoveLi