undefined | unit 4 arrays

PPS

Unit – 4ArraysQ1. Explain array declaration and initialization?A1. Array is a data structure which stores the collection of similar types of element in consecutive memory locations. Indexing of array always start with ‘0’ where as non-graphical variable ‘\0’ indicates the end of array. Syntax for declaring array is data type array name[Maximum size];

Data types are used to define type of element in an array. Data types are also useful in finding the size of total memory locations allocated for the array.

All the rules of defining name of variable are also applicable for the array name.

Maximum size indicates the total number of maximum elements that array can hold.

Total memory allocated for the array is equal to the memory required to store one element of the array multiply by the total element in the array.

In array, memory allocation is done at the time of declaration of an array.

Example:

Sr. No.	Instructions	Description
	#include<stdio.h>	Header file included
2.	#include<conio.h>	Header file included
3.	void main()	Execution of program begins
4.	{	Memory is allocated for variable i,n and array a
5.	inti,n,a[10];	Memory is allocated for variable i,n and array a
6.	clrscr();	Clear the output of previous screen
7.	printf("enter a number");	Print “enter a number”
8.	scanf("%d",&n);	Input value is stored at the addres of variable n
9.	for(i=0;i<=10;i++)	For loop started from value of i=0 to i=10
10.	{	Compound statement(scope of for loop starts)
11.	a[i]=n*i;	Result of multiplication of n and I is stored at the ith location of array ieasi=0 so it is stores at first location.
12.	printf("\n %d",a[i]);	Value of ith location of the array is printed
13.	}	Compound statement(scope of for loop ends)
14.	printf("\n first element in array is %d",a[0]);	Value of first element of the array is printed
15.	printf("\n fifth element in array is %d",a[4]);	Value of fifth element of the array is printed
16.	printf("\n tenth element in array is %d",a[9]);	Value of tenth element of the array is printed
17.	getch();	Used to hold the output screen
18.	}	Indicates end of scope of main function

Array Intialization: int a[3] = {2, 3, 5}; charch[10] = "Data" ; float x[3] = {2.5, 3.50,489.98} ; Q2. Explain bound checking arrays?A2. One Dimensional Array:The array which is used to represent and store data in a linear form is called as 'single or one dimensional array.'Syntax:data-typearray_name[size]; Example 2: int a[3] = {2, 3, 5}; charch[10] = "Data" ; float x[3] = {2.5, 3.50,489.98} ; Total Size of an array(in Bytes) can be calculated as follows: total size(in bytes) = length of array * size of data type In above example, a is an array of type integer which has storage size of 3 elements. One integer variable occupies 2 bytes. Hence the total size would be 3 * 2 = 6 bytes.Memory Allocation :

P1: Program to display all elements of 1-D array. #include<stdio.h>
#include<conio.h>
void main()
{
int a[20];
intn,i;
printf("\n Enter the size of array :");
scanf("%d",&n);
printf("size of array is %d",n);
printf("\n Enter Values to store in array one by one by pressing ENTER :");
for(i=0;i<n;i++)
{
scanf("%d",&a[i]);
}
printf("\n The Values in array are..");
for(i=0;i<n;i++)
{
printf("\n %d",a[i]);
}
getch();
}

P2: Program to copy 1-D array to another 1-D array#include <stdio.h>#include<conio.h> void main(){int n, i, j, a[100], b[100];// a is original array and b is copied array printf("Enter the number of elements in array a\n");scanf("%d", &n); printf("Enter the array elements in a\n"); for (i= 0; i< n ; i++)scanf("%d", &a[i]); /* Copying elements from array a into array b */ for (i =0;i<n;i++)b[i] = a[i]; /* Printing copied array b. */ printf("Elements of array b are\n"); for (i = 0; i< n; i++)printf("%d\n", b[i]); getch();} Output:

P3:Program to find reverse of 1-D array#include <stdio.h>#include<conio.h> void main(){int n, i, j, a[100], b[100];// a is original array and b is reversed array printf("Enter the number of elements in array\n");scanf("%d", &n); printf("Enter the array elements\n"); for (i= 0; i< n ; i++)scanf("%d", &a[i]); /* * Copying elements into array b starting from end of array a */ for (i = n - 1, j = 0; i>= 0; i--, j++)b[j] = a[i]; /* Printing reversed array b. */ printf("Reverse array is\n"); for (i = 0; i< n; i++)printf("%d\n", a[i]); getch();}Output:

Multi Dimensional Array

1-D array has 1 row and multiple columns but multidimensional array has of multiple rows and multiple columns.Two Dimensional array:It is the simplest multidimensional array. They are also called as matrix.Declaration: data-typearray_name[no.of rows][no. of columns];Total no of elements= No.of rows * No. of Columns Example 3: inta[2][3]This example illustrates two dimensional array a of 2 rows and 3 columns.

Total no of elements: 2*3=6 Total no of bytes occupied: 6( totalno.of elements )*2(Size of one element)=12Initialization and Storage Representation:In C, two dimensional arrays can be initialized in different number of ways. Specification of no. of columns in 2 dimensional array is mandatory while no of rows is optional.int a[2][3]={{1,3,0}, // Elements of 1st row {-1,5,9}}; // Elements of 2nd row OR int a[][3]={{1,3,0}, // Elements of 1st row {-1,5,9}}; // Elements of 2nd row OR int a[2][3]={1,3,0,-1,5,9}; Fig. 3 gives general storage representation of 2 dimensional array

Eg 4. int a[2][3]={1,3,0,-1,5,9}

Accessing Two-Dimensional Array Elements:An element in 2-dimensional array is accessed by using the subscripts i.e. row index and column index of the array. For example:intval= A[1][2];The above statement will access element from the 2nd row and third column of the array A i.e. element 9.Q3. Write a program to display all the elements in the array?A3. #include<stdio.h>
#include<conio.h>
void main()
{
int a[20];
intn,i;
printf("\n Enter the size of array :");
scanf("%d",&n);
printf("size of array is %d",n);
printf("\n Enter Values to store in array one by one by pressing ENTER :");
for(i=0;i<n;i++)
{
scanf("%d",&a[i]);
}
printf("\n The Values in array are..");for(i=0;i<n;i++)
{
printf("\n %d",a[i]);
}
getch();
}

Q4. Explain multidimensional arrays?A4. 1-D array has 1 row and multiple columns but multidimensional array has of multiple rows and multiple columns.Two Dimensional array:It is the simplest multidimensional array. They are also called as matrix.Declaration: data-typearray_name[no.of rows][no. of columns];Total no of elements= No.of rows * No. of Columns Example 3: inta[2][3]This example illustrates two dimensional array a of 2 rows and 3 columns.

.Eg 4. int a[2][3]={1,3,0,-1,5,9}

Accessing Two-Dimensional Array Elements:An element in 2-dimensional array is accessed by using the subscripts i.e. row index and column index of the array. For example:intval= A[1][2];The above statement will access element from the 2nd row and third column of the array A i.e. element 9.Q5. Explain storage and initialization?A5. Initialization and Storage Representation:In C, two dimensional arrays can be initialized in different number of ways. Specification of no. of columns in 2 dimensional array is mandatory while no of rows is optional.int a[2][3]={{1,3,0}, // Elements of 1st row {-1,5,9}}; // Elements of 2nd row OR int a[][3]={{1,3,0}, // Elements of 1st row {-1,5,9}}; // Elements of 2nd row OR int a[2][3]={1,3,0,-1,5,9}; Fig. 3 gives general storage representation of 2 dimensional array

Eg 4. int a[2][3]={1,3,0,-1,5,9}

Q6. Explain character array and strings?A6. If the size of array is n then index ranges from 0 to n-1. There can be array of integer, floating point or character values. Character array is called as String.

0 1 2 3 4

This example illustrates integer array A of size 5.

Array index ranges from 0 to 4.

Elements of array are {10, 20, 40, 5, 25}.

Arrays can be categorized in following types

One dimensional array

Multi-Dimensional array

These are described below.The abstract model of string is implemented by defining a character array data type and we need to include header file ‘string.h’, to hold all the relevant operations of string. The string header file enables user to view complete string and perform various operation on the string. E.g. we can call ‘strlen’ function to find length of string, ‘strcat’ to concatenate two string, ‘strcpy’ to copy one string to another, ‘strrev’ to reverse the string. The definitions of all these functions are stored in the header file ‘string.h’. So string functions with the user provided data becomes the new data type in ‘C’.

String data typeTo use the functions related to strings, user only need to include ‘string.h’ header file. All the definitions details of these functions are keep hidden from the user, user can directly use these function without knowing all the implementation details. This is known as abstraction or hiding.Q7. Write a program to find the length of the string?A7. #include <stdio.h>int main() {char s[] = "Programming is fun";inti;for (i = 0; s[i] != '\0'; ++i); printf("Length of the string: %d", i);return 0;}Run CodeOutputLength of the string: 18Q8. How do you access the elements in the array?A8. An element in 2-dimensional array is accessed by using the subscripts i.e. row index and column index of the array. For example:intval= A[1][2];The above statement will access element from the 2nd row and third column of the array A i.e. element 9. Q9. Write a program to find the average of n numbers?A9. #include <stdio.h>int main() {char s[] = "Programming is fun";inti;for (i = 0; s[i] != '\0'; ++i);printf("Length of the string: %d", i);return 0;}Run CodeOutputLength of the string: 18Q10. Write a program to reverse a string?A10. #include <stdio.h>int main(){char s[1000], r[1000];int begin, end, count = 0; printf("Enter a string to reverse \n");gets(s); // Calculating string length while (s[count] != '\0')count++; end = count - 1; for (begin = 0; begin < count; begin++) {r[begin] = s[end];end--; } r[begin] = '\0'; printf("Reverse of entered string is %s\n", r); return 0;}

Sign Up