palindrome prime-numbers palindromes palindrome-string algorithm-sort-heap-sort-algorithm arrays-merge-two-arrays-and-sort biggest-number-in-array convert-decimal-to-binary factorial-example fibonacci-series-example find-missing-number-in-array find-second-largest-number-in-array how-to-encrypt-decrypt-keys-in-config keywords-virtual-override-new-example list-the-files-in-a-directory prime-number-example program-to-swap-2-numbers-using-3rd-number