C Primer Plus (5th Edition)

https://www.amazon.com/Primer-Plus-5th-Stephen-Prata/dp/0672...

My version was older than the Amazon version as I learned in 1987.

You declared the array wrong, correct way:

int a[7]={1,2,3,4,5,6,7};

Also you cannot declare two as rename the second:

int a=len/2; 

to something else.

Might I suggest some good C Books? I think you need to learn C before coding in it.

• The C Programming Language
• C Primer Plus

Reference Style - All Levels

• The C Programming Language (2nd Edition) - Brian W. Kernighan and Dennis M. Ritchie
• C: A Reference Manual (5th Edition) - Samuel P. Harbison and Guy R. Steele
• C Pocket Reference (O'Reilly) - Peter Prinz, Ulla Kirch-Prinz
• C - Traps and Pitfalls - Andrew R. Koenig (Bell Labs)
• The comp.lang.c FAQ - Steve Summit

Beginner

• Programming in C (3rd Edition) - Stephen Kochan
• C Primer Plus (5th Edition) - Stephen Prata
• C Programming: A Modern Approach (2nd Edition) - K. N. King
• A Book on C - Al Kelley/Ira Pohl
• The C Book (Free Online) - Mike Banahan, Declan Brady and Mark Doran
• Practical C Programming (3rd Edition) - Steve Oualline
• C: How to Program (6th Edition) - Paul Deitel & Harvey M. Deitel
• Head First C - David & Dawn Griffiths
• Beginning C (5th Edition) - Ivor Horton

Intermediate

• Object-oriented Programming with ANSI-C (Free PDF) - Axel-Tobias Schreiner
• C Interfaces and Implementations - David R. Hanson
• The C Puzzle Book - Alan R. Feuer
• The Standard C Library - P.J. Plauger
• 21st Century C - Ben Klemens
• Algorithms in C - Robert Sedgewick
• Pointers on C - Kenneth Reek
• Pointers in C - Naveen Toppo, Hrishikesh Dewan
• Understanding and Using C Pointers - Richard M Reese

Above Intermediate

• Expert C Programming: Deep C Secrets - Peter van der Linden
• Advanced C Programming by Example - John W. Perry
• Advanced Programming in the UNIX Environment - Richard W. Stevens

Uncategorized Additional C Programming Books

• Essential C (Free PDF) - Nick Parlante
• The new C standard - an annotated reference (Free PDF) - Derek M. Jones

This is a common mistake amongst newer C/C++ developers. The scanf function detects you hitting the ENTER/RETURN key to signal the end of input, but it also catches the \n character as well at the end of the input string, so you essentially get two RETURNS being detected.

Please read up on an example of using fgets and sscanf here:

http://www.linuxforums.org/forum/programming-scripting/67560-problem-scanf.html


It will resolve this issue very quickly for you. In the meantime, I strongly urge you to check out this book:

http://www.amazon.com/Primer-Plus-5th-Stephen-Prata/dp/0672326965


It is the most commonly used C programming book in high school and colleges in North America, and has TONS of examples for you to work through, including this specific program you demonstrated above. The print version has more examples than the e-book, so I would just cough up the $30.00 for the printed version.

Good luck!