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reverse a string - word by word - revisited

Hmm, I agree that swapping the string and
then swapping each word is probably the
best solution, but I would disagree that
swapping the words is impossible (or even
that hard or obscure).  The obvious (if
somewhat nasty) solution is to create a
linked list, traverse the string forwards
adding a pointer to each word to the linked
list, and then simply traverse the list
backwards adding the words to the new string
as you go.

I can't leave statements like "impossible"
alone heh :)

Ryan Mooney
Tuesday, November 26, 2002

You are forgetting that the problem required that the string be reversed in place.

Apart from a couple of pointers, the original solution (reverse the string in place, then reverse the words in place) requires only an extra sizeof(char) to temporarily buffer a single character as characters are swapped.

Dominic Cooney
Saturday, November 30, 2002

The extra char is unnecessary as well. Using integer arithmetic, this code snippet will change two characters in situ:

a=a xor b
b=a xor b
a=a xor b

Nordic Light
Tuesday, December 03, 2002

xor's are for sissies:

a = a+b
b = a-b
a = a-b

b
Monday, December 30, 2002

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