Chapter 09

Problem Solving and Program Design in C (5th Edition) by Jeri R. Hanly and Elliot B. Koffman

CP 202 Chapter 9

Declaring String  

A string in C is implemented as an array of char. Declaring a string variable is the same as declaring an array of char: char string_var[30];

Declaring and Initializing String 

Initializing string variables: char str[10] = “Hello to”; It will look in the memory like: [0] [1] [2] [3] [4] [5] [6] [7] [8] [9]

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o \0

The str[8] contains the character ‘\0’, the null character, that marks the end of a string. This means that str can contain only 9 characters. If you want to work with an array of char as string, you need to add the null character at the end.

Arrays of String 

An array of strings is a two-dimensional array of characters in which each row is one string. char month[12][10] = {“January”, “February”, “March”, “April”, “May”, “June”, “July”, “August”, “September”, “October”, “November”, “December”};

Strings and I/O Functions 

You need to use the placeholder %s with the string variables.

char str[20] = “Hello to”;

char month[12][10] = {“January”, “February”, “March”, “April”, “May”, “June”, “July”, “August”, “September”, “October”, “November”, “December”}; printf(“%s\n”, str); hello to

printf(“ %c%c \n”, str[4], month[1][3]); or printf(“%s\n”, month[10]);

// // // November

Strings and I/O Functions EXAMPLE

Strings and I/O Functions EXAMPLE (OUTPUT)