17.1 - Swap two numbers without temp using artihmatic and xor
17.2 - Check if tic tac toe board is a winner
17.3 - Compute trailing zeros of factorials using dynamic programming
17.5 - Needs updating
17.6
17.6 - Minimize sortable area of an array
17.7 - To string numbers up to 100000
17.4 - Find subsequences with largest sums
17.9 - Count word frequency in a book
17.10 - Encode xml
17.11 - Create rand7 from rand5