Programming and Data Structures

W orking w ith Strings &

Standard Functions

CHAPTER OUTLINE

8.1

Introduction

8.2

Declaration and Initialization of String

8.3

Display of Strings with Different Formats

8.4 String Standard Functions

8.5 Applications of Strings

Exercises

8.1 INTRODUCTION

In C language the group of characters, digits, and symbols enclosed within quotation marks are

called as string. The string is always declared as character arrays. In other words character arrays

are called Strings. To manipulate text such as words and sentences normally strings are used. Every

string is terminated with 1 \

0' (NULL) character. The NULL character is a byte with all bits at logic

zero. Hence, its decimal value is zero.

For Example

char name[ ] = { 1I //fN///D/#/I #//A/#/\0/};

Each character of the string occupies 1 byte of memory. The last character is always ' \0'. It is not

compulsory to write 1 \0' in string. The Compiler automatically puts 1 \0' at the end of the character

array or string. The characters of string are stored in contiguous (neighboring) memory locations.

Table 8.1 given below shows uh e storing of string elements in contiguous memory locations.

Table 8.1 Memory map of string.

I N D I A

\0

5001 5002 5003 5004

5005 5006

8.2 DECLARATION AND INITIALIZATION OF STRING

The above string can also be initialized as follows,

char name[ ]= " INDIA";

The C compiler inserts the NULL (\0) character automatically at the end of the string. So

initialization of NULL character is not essential.

Also,