1Strings10/24/20072Opening Discussion■Let's look at solutions to the interclass problem.■Denim Group presentation in HAS 340 at 5pm.■Answers to the minute essay&a – int**b – int*(b+2) – int&(*b) – int**(&a) – int■Do you have any questions about the assignment?3Strings■I'm deviating from the order of the book for this because I want us to be able to use strings. We'll go into more detail later.■A string in C is a null terminated array of characters. That is to say it is an array of characters with the value zero stored after the last character.■Note this is the value zero, not the character zero. Since zero is not a valid character in ASCII this can be used to end the string.4Initializing String Variables■When you declare an array of chars you can set it equal to a string literal.■You don't have to provide the length of the array unless you want extra space in the string.5Strings as Pointers■Many functions will treat strings as a char* or a const char* instead of a char[]. As we'll see later, this makes sense because arrays and pointers are extremely similar in many ways.■When you write a function that deals with a string you can have it take either a char* or a char[]. I will probably use char* out of habit.6Writing some String Functions■Let's write one or two functions that deal with strings.7String Library■Obviously, many people need these functions. As you would expect, they exist in a library for exactly this reason.■You can include string.h and look in the man pages to see all the different things that the C libraries allow you to do with strings.■While it is good to know how to manipulate strings, you will probably use the libraries for most basic manipulations.8String I/O■In printf and scanf you use %s to signify a string.■For scanf it only reads one word and you don't need to put the & in front of the variable because an array is like a pointer.■The fgets function can be used to read in a full line.9Minute Essay■Write a function that takes a string as input and returns the number of lower case letters in the string.■Denim Group presentation in HAS 340 at 5pm.■Interclass Problem – Play with strings some and write a program that has the user input a string, then does some manipulations and prints out an altered string. You can pick the
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