What is wrong with using the available tools and functions? Unless this is homework, it is a silly requirement.
in reply to reverse a string in place
And if it is homework, it still is silly.
A program should be light and agile, its subroutines connected like a string of pearls. The spirit and intent of the program should be retained throughout. There should be neither too little or too much, neither needless loops nor useless variables, neither lack of structure nor overwhelming rigidity." - The Tao of Programming, 4.1 - Geoffrey James
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