Pert ke 1 - Introduction to Linked List - 2101680123 - Milliady Kusnadi The Bu Hiap

Introduction to Linked List

A.   Structure

•      Structure is basically a user-defined data type that can store related information (even of different data types) together, while an array can store only entities of same data types.

•      It is a collection of variables under a single name.

•      The variables within a structure are of different data types and each has a name that is used to select it from the structure.

·        Structure Declaration

struct tdata {

          int   age;

          char  name[100];

          float score;
};

struct tdata {

          int   age;

          char  name[100];

          float score;

};

•      The code above defines a structure named tdata which has three members: age (int), name (char[]) and score (float).

•      Creating a variable of structure is similar to create a variable of primitive data type.

          tdata x;                 // a variable of tdata

          tdata arr[100];      // an array of tdata

You also can define a structure as well as declare variables.

struct tdata {

          int   age;

          char  name[100];

          float score;

} a, b;

·        Structure Assignments

tdata x;

You can use operator . (dot) to access member of x

x.age = 17;

strcpy(x.name, “andi”);

x.score = 82.5;

·        Nested Structure

You also can have a structure as a member of another structure

struct profile {

          int   age;

          char  name[100];

};

struct student {

          struct profile p;

          int  score;

          char grade;

};

B.   Array of Structure

You also can have an array of structure.

struct profile {

          int   age;

          char  name[100];

};

struct student {

          struct profile p;

          int  score;

          char grade;

};

C.   Memory Allocation: Dynamic

If you need to allocate memory dynamically (in runtime), you can

use malloc in C/C++. To de-allocate you can use free.

int  *px = (int *) malloc(sizeof(int));

char *pc = (char *) malloc(sizeof(char));

*px = 205;

*pc = ‘A’;

printf( “%d %c\n”, *px, *pc );

free(px);

free(pc);

·        Linked List Introduction

Linked list is a data structure that consists of a sequence of data

records such that each record there is a field that contains a

reference to the next record in the sequence.

Example of a list whose nodes contain two fields:

an integer value and a link to the next node.

Linked list which node contain only a single link to other node is

called single linked list.

·        Linked List versus Array

Array:

•         Linear collection of data elements

•         Store value in consecutive memory locations

•         Can be random in accessing of data

Linked List:

•         Linear collection of nodes

•         Doesn’t store its nodes in consecutive memory locations

•         Can be accessed only in a sequential manner

D.   Summary

•      Structure is a collection of variables under a single name

•      The variables within a structure are of different data types and each has a name that is used to select it from the structure

•      Linked list is a data structure that consists of a sequence of data records such that each record there is a field that contains a reference to the next record in the sequence.