Comments on: Make your own atoi() function in C http://blog.breadncup.com/2009/12/21/make-your-own-atoi-function-in-c/ Mon, 02 Jan 2012 07:11:27 +0000 hourly 1 http://wordpress.org/?v=3.3 By: Breadncup http://blog.breadncup.com/2009/12/21/make-your-own-atoi-function-in-c/comment-page-1/#comment-3680 Breadncup Sat, 26 Nov 2011 16:47:08 +0000 http://blog.breadncup.com/?p=225#comment-3680 k holds an integer, and it is recalculated by looking at the each character from the beginning given p. (*p) tells you the character's ASCII code and '0' as well. The difference gives the actual integer number. k*10 is shifting of previous value. For example, if p is given by "425", The first calculation of k = 0*10 + (*p) - '0' = 0 + 52-48 = 4 The next calculation of k = 4*10 + (*p) - '0' = 40 + 50 - 48 = 42 The final calculation of k = 42*10 + (*p) - '0' = 420 + 53-48 = 425 Character ASCII code of "4" is 52, "2" is 50, "5" is 53, and "0" is 48. Hope this would help you, Daniel k holds an integer, and it is recalculated by looking at the each character from the beginning given p. (*p) tells you the character’s ASCII code and ’0′ as well. The difference gives the actual integer number. k*10 is shifting of previous value.

For example, if p is given by “425″,

The first calculation of k = 0*10 + (*p) – ’0′ = 0 + 52-48 = 4
The next calculation of k = 4*10 + (*p) – ’0′ = 40 + 50 – 48 = 42
The final calculation of k = 42*10 + (*p) – ’0′ = 420 + 53-48 = 425

Character ASCII code of “4″ is 52, “2″ is 50, “5″ is 53, and “0″ is 48.

Hope this would help you,
Daniel

]]> By: Xenon http://blog.breadncup.com/2009/12/21/make-your-own-atoi-function-in-c/comment-page-1/#comment-3679 Xenon Sat, 26 Nov 2011 16:22:44 +0000 http://blog.breadncup.com/?p=225#comment-3679 thanks for help can you please explain this string ?: => k = k*10 + (*p) - '0'; thanks for help
can you please explain this string ?:

=> k = k*10 + (*p) – ’0′;

]]> By: YOUNGWHAN SONG (송영환) http://blog.breadncup.com/2009/12/21/make-your-own-atoi-function-in-c/comment-page-1/#comment-743 YOUNGWHAN SONG (송영환) Tue, 22 Dec 2009 11:51:04 +0000 http://blog.breadncup.com/?p=225#comment-743 <span class="topsy_trackback_comment"><span class="topsy_twitter_username"><span class="topsy_trackback_content">New blog post: Make your own atoi() function in C http://blog.breadncup.com/2009/12/21/make-your-own-atoi-function-in-c/</span></span> New blog post: Make your own atoi() function in C http://blog.breadncup.com/2009/12/21/make-your-own-atoi-function-in-c/

]]> By: Daniel (Youngwhan) http://blog.breadncup.com/2009/12/21/make-your-own-atoi-function-in-c/comment-page-1/#comment-2298 Daniel (Youngwhan) Tue, 22 Dec 2009 11:51:04 +0000 http://blog.breadncup.com/?p=225#comment-2298 <span class="topsy_trackback_comment"><span class="topsy_twitter_username"><span class="topsy_trackback_content">New blog post: Make your own atoi() function in C http://blog.breadncup.com/2009/12/21/make-your-own-atoi-function-in-c/</span></span> New blog post: Make your own atoi() function in C http://blog.breadncup.com/2009/12/21/make-your-own-atoi-function-in-c/

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