One-Dimensional Arrays in C Programming Language with Examples


What is an Array in C?

In the programming language C, an array is a collection of values of a given data type. Arrays can be created from any of the C data types, such as "int," "float," and "char." Arrays can only hold data of their designated type: for example, an integer array can only hold integer values.

How does an array differ from a variable? When we declare array, it allocates a contiguous memory location for storing values, whereas two or three variables of same data-type can be given random locations. Arrays store data under a single variable name and index.

There are different types of arrays:

  1. One-dimensional array (Also known as 1D array).
  2. Two-dimensional array (Also known as 2D array).
  3. Multi-dimensional array.

This tutorial discusses the one-dimensional array.

Declaration of One Dimensional Arrays:

To declare a one-dimensional array in C, use the following syntax: data_type array_name[width];

Example: Declare an array that can store the roll numbers of eight students in a class, for the purpose of taking roll.

Answer: int roll[8];

In our example:

  • int specifies the type if the variable. In this example, an integer;
  • roll specifies the given name of the variable;
  • [8] is the value;
  • The brackets ([ ]) tell the compiler that what follows is an array, and the number in the brackets specifies how many elements (values in any array are called elements) it can store. This number is also the size of array.

In this example we have declared an integer array named“roll” that can store the roll numbers of eight students.

You can see the memory arrangement of the above declared array in the following image:

How a 1D array is stored in memory. You can access any value in the array based on the index.
How a 1D array is stored in memory. You can access any value in the array based on the index.

C Array Assignment and Initialization

We can assign values to arrays just as we assign them to variables. We can initialize an array (assign its initial values) just was we initialize a variable. Value can be assigned to an array at the time of declaration or during runtime. Let’s look at each approach.

The syntax for assigning value to an array is: data_type array_name[size]={list of values};

int arr[5]={1,2,3,4,5};
int arr[]={1,2,3,4,5};

Both these examples are valid ways of declaring an integer array named “arr,” stating that it can hold five elements, and initializing it by listing the values it holds. The first example mentions the size of the array—[5]—and assigns the values to the elements by putting the values in curly brackets, separating each element’s value with a comma.

In the second example we left the “size” field blank, but we provided values for five elements. When we only give element values without specifying the size of an array, then the C compiler automatically assumes an array size based on the number of element values given (in this case, five).

Initializing an Array by Assigning Individual Variables

There is one more way to initialize an array C programming. In this method we can assign values to each individual element of an array. See the example below.



void main()
int arr[5],i;

printf("Value in array arr[0] : %d\n",arr[0]);
printf("Value in array arr[1] : %d\n",arr[1]);
printf("Value in array arr[2] : %d\n",arr[2]);
printf("Value in array arr[3] : %d\n",arr[3]);
printf("Value in array arr[4] : %d\n",arr[4]);

	printf("Value in array arr[%d] : %d\n",i,arr[i]);


This print-out shows you how the initial values are stored in this array in C.
This print-out shows you how the initial values are stored in this array in C.

In this example, we have assigned individual values to the integer array, just as we would to an integer variable. We called the value of each array element individually, and used a for loop operation so it would be clear for beginner C programmers.

This example shows we can assign individual values to array elements, and call the values whenever we need them.

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Comments 79 comments

Josh 7 years ago

You mention only 1-dimensional arrays, which are quite basic and simple to understand.

Rather, I think that most users would be looking for help concerning 2-dimensional and multi-dimensional arrays, as these are the ones that are a lot harder to wrap your mind around.

nicomp 7 years ago

An array dimensioned as [5] only has elements 0 through 4. It has no element [5]. Your code is incorrect.

R.Dhnanalakshmi 7 years ago

I Have some information in 'c'program,but more detail in array concept please sir.

Thank Sir

nataraju 7 years ago

char a[]={1,2,3,4,5,6,7,4,33,44,2,1,54,6,7,87,5,4,3,5,7,6,54,4,4,3};

char a1[]={1,2,3,4,5,6,7,4,33,44,2,1,54,6,7,87,5,4,3,5,7,6,54,4,4,3};

char a2[]={1,2,3,4,5,6,7,4,33,44,2,1,54,6,7,87,5,4,3,5,7,6,54,4,4,3}

char a3[]={1,2,3,4,5,6,7,4,33,44,2,1,54,6,7,87,5,4,3,5,7,6,54,4,4,3}

char a4[]={1,2,3,4,5,6,7,4,33,44,2,1,54,6,7,87,5,4,3,5,7,6,54,4,4,3};

char a5[]={a,a1,a2,a3,a4};

a5 is correct or not

how to store a to a4 in to another array

alia 7 years ago

how to write programs using array???can u give some examples

anne khandelwal 6 years ago

how to write a program to generate prime numbers from 1to 100??with explanation..plz help me..

jhesmer 6 years ago

plzz create a program that will input 10 numbers and will output the 10 numbers from least to greatest

example input: example output:

9 0

0 1

8 2

1 3

7 4

2 5

6 6

3 7

5 8

4 9

plzz do e-mail it to me:

a big thankzz to everyone!!

zeke 6 years ago

could u create a program which will input 15 car names

and will get the choice,quantity,payment and change of the costumer..please e-mail it to me:

thank you & god bless...

LeAnn 6 years ago

I really need some help!

i have to:

1. create an array of 7 integers

2. ask user to give the values of its elements and fill the array

3. find the minimum of values in the array and print it

please help!

email it to me @

it is due in 6 hours. I am trying my best to do this, but i'm having a lot of difficulties.


an 6 years ago

these has ben a good help to me! thanks to you! im having a hard time understanding all the cides and terms in our programming subject! our prof gave us an assign. in which we will create a program ussing array!!!!!can u help me? i need it asap thankssssss

madbones 6 years ago

harigatou gozaimasu!

prakash bannadabhavi 5 years ago


using namespace std;

int main()


int x;

int y;

int array[8][8]; // Declares an array like a chessboard

for ( x = 0; x < 8; x++ ) {

for ( y = 0; y < 8; y++ )

array[x][y] = x * y; // Set each element to a value



kaushik 5 years ago

i need more tutorial session suggest us more

vinodh 5 years ago

int a[]={0,1,2,3,4}

i want to display all this in increment way.. tell me the short and simple way

christiyal jansi rani 5 years ago

Respected sir/Madam! I am christi! plz one help doupt for you sir! array initialazation reading writing program ! Its very urgent! plz Condect My ID Name was

miles 5 years ago

hi can u create a program that will read 10 characters(char) and store in an array.And display the count of each character being stored (please see the sample illustration below).

Sample Illustration:

char A[5];







The counter:




miles 5 years ago

Email me the answer please...

enzoh_22 5 years ago

write a program containing a function that will compute and display the answer of various statistical measurement like a. combination and permutation b. mean, median, mode.

e-mail to thnks

prashant kedar 5 years ago

i like

bulbul 5 years ago

sir\madam actually i need ur help to do the programing of multidimensional array.The programme is to evaluate each student total value and final total value.

plz help me how can i do this program by using which logic

My emailid is:

ritesh 5 years ago

in 1-D array i want access the all array elements to the other functions too other functions and i want to doing actually quick sort so i have change index of array all times. im trying so much but not getng output. so plz tell me as soon as fast possible. i need it.

my emailid :

Bikram anand ,barari 5 years ago

Sir, this tutorial is nice but i have requested to should add some more eaisy example with output.thanx

anne 5 years ago

thank u so much,,its such a great help!!

mamatha.k 5 years ago

plese try to explian with some more examples

julie 5 years ago


michelle 5 years ago

Ma'am/Sir i need your help. please help me regarding my assignment, I want to know more about's the formula:

char a[11]="Boring";

printf("Index 0 has %c\n",a[0];

printf("Index 1 has %c\n",a[1];

printf("index 2 has %c\n",a[3];

printf("Index 3 has %c\n",a[4];

printf("Index 4 has %c\n",a[5];

printf("Index 5 has %c\n",a[6];

printf("Index 6 has %c\n",a[7];

printf("Numerically,the a[6] is %d\n",a[6]);


a. How many slots/indexes does this array have?

b. How many characters, counting the null character at the end,does this array hold?

c. The number of an index is also called an index. What is the lowest index?

d. What is the highest index for this array?

e. Is the number for the highest index the same as that for the number of indexes?

f. What is stored in the last index as a character,that is, in an index number 5?

g. What is stored in the last index numerically? All strings should have this null character stored in its last index to signal the end of the string.

I hope you can help me regarding my problem. This is my email id:

nikhil 5 years ago

how to make a programe to find out the greatest element in an array in c languae !!

snkhan120 profile image

snkhan120 5 years ago

array is a heart of programming

vishal gurhale 5 years ago

i want detail in array

like as

how initialize of array.

and how to work array in program

deepak vaishnav 5 years ago

nice programming and any another program,

kavitha 5 years ago

i want answer this question please.

write a program to copy the contents of one array into another array in the reverse order.please answer to the question

pooja 5 years ago

i like thankyou so much

elkan 5 years ago

Pls help me

Write a C program that displays an array of 10 different double numbers. The numbers should be values that you assign to the array by hard-coding them in the main().

The numbers should be displayed using a function that you write called DisplayNumbers.

Write another function called ReverseArrayNumbers that:

creates a second array of the same size as the first one

copies the numbers from the first array into the new array in reverse order.

Display the numbers in the new array by using the DisplayNumbers ...

email it to:

Thank you

shonah 5 years ago

pls help a sister out

Write a C program that displays an array of 10 different double numbers. The numbers should be values that you assign to the array by hard-coding them in the main().

The numbers should be displayed using a function that you write called DisplayNumbers.

Write another function called ReverseArrayNumbers that:

creates a second array of the same size as the first one

copies the numbers from the first array into the new array in reverse order.

Display the numbers in the new array by using the DisplayNumbers ...

email it to:

Thank you

jyoti 5 years ago

plz give me some program in character an array

kalaiselvi 5 years ago

i want this program multipulation of array, pls send my mail id my mail id is

Jaiyaishri 5 years ago

good's eassy to lurn & understand.

Keya Mondal 5 years ago

hi, my email id

please help me about stack

abhi 5 years ago

i m facing problem to WAP in c language using Array.2d,multi d.plz give me good idea to understood

lee 5 years ago

please help me how to fill matrix arr[i][j] with elements which i could later round to nearest integer.!!

ahmad gill 5 years ago

who can find solution???????



void mtrx_sort(int ary[][3]); //function prototype


{ clrscr();

int x,y=2;

int ary[3][3];


ziaah 5 years ago

Write a c++ program?

a.declare an integer array of 5?

lavanya 5 years ago

write a program to get marks of 5 different subjects for 10 students and print the same.

janu 5 years ago

how a print a character in a array "multiple character"

alvina 5 years ago

can any one help me now? i need a program which can read 25 integer values n print it in ascndng ordr

lavanya 5 years ago

pls any one send this program answer ,Twenty five numbers are entered through the keyboard into an arry.Write a program to find out how many of them are positive,how many are negative,how many are even and how many are odd.

Ana 5 years ago

please help me

write a complete program that will ask 10 integer numbers using an array. the program will display the values in revers order.


rajib 5 years ago

plz write a program to find 1st and 2nd largest no using array

lemiey 5 years ago

my question is : how to write a program that can read 10 integer values into an array and find the total for that array in the program,write 3 function:a function to read value, a function to find the total of element values and a function to print value.

Saroar Hossain 5 years ago

Searching one dimensional array:

Write a program that takes 10 values from the user, stores it in an array and allows the user to look for a value in that array (after the array is created, ask the user for the value they want to search for in the array, write a searching algorithm which looks for that value in the array and if found tells the user about its location [index no.] if not found informs the user that no matching results were found)

Matrix multiplication using

I am really very confused. Can you please help me solving this problem? Please

momai 5 years ago

...kindly help me to do programming about phonebook using the array program.....

ash 5 years ago

how to write up a program that will store five random integer numbers in an array and find the highest and lowest number stored and display the highest and lowest value in c++ programming

pooja.i 5 years ago

write a c program to entering a 3 nos and print 3 nos using array

ishaq 5 years ago

please make a program which show yout id is vaild or not

Shalini 5 years ago

Write the code for the below, the input which we give looks like this.

enter the number of element


enter the number of materials


enter the material details



details of material 1

thickness angle material

details of material 2

thickness angle material

sonali ananthre 5 years ago

please help me to sort

sruthi 5 years ago

write a programme for multi dimentional array...........

babegirl15 5 years ago

can you help me with this?

Assigning values to array through input operation.

like this.

content of array

locaion value

o 1000

1 0

2 0

3 0

4 0

Datay entry using array

Enter location: 0

Enter value:

Accept another value?

please email me the answer

sam 4 years ago

how to print an element a[3] of array a[10] if values has been entered

Emmanuel 4 years ago


I need someone to help me solve this questions (C programming).

You have a two-dimensional array [ 4 ] [5 ].

a) make a program that calculates the sum of the elements.

b) make a program that finds the entered value from the array and prints out ”success” if found and ”empty” if not found.

c) change the exercise b so that it prints out the place from where the program found the entered value .

Example of initializing a two-dimensional array:

int array [ 4 ] [5 ] =

{ { -2, 5, -7, 2, 8},

{ 80, 32, 4, 5, 6},

{ -1, 0, 4, 82, 6},

{ 3, -5, 4, 7, 8}


Send the solution to my email address:

don 4 years ago

how to reverse a printout of an array?

mkeith profile image

mkeith 4 years ago from United States

Your "Memory Arrangement" in your diagram is likely wrong. Computers have been running a 32-bit os since the mid to late 90's. If you are programming on a windows machine then an 'int' variable type gets 4 bytes of data, not 2. If you are programming for some other type of processor that only has a 16 bit integer (word size) then this is fine, but you need to declare this as it might confuse others.

Java Programs profile image

Java Programs 4 years ago from India

one of the best article i have seen for c programming dealing with arrays ..... keep the good work up ..

indu 4 years ago

plzz tell me how to proiduce nested loop??

ridhima 4 years ago

plzz tell me a c++ program to multiply a number x upto n terms...????

hhh...d 4 years ago

write a program read the integer 10 element into an array and display it in reverse order?

سووووووووسو 4 years ago

consider the following java statement double [] A1 = new double [7]; int A2 [],A3; A2 ={2,4,10);

1) how many arrays in the previous code?name them

2)what is the data type of A3?

3)draw the memory address for A1,A2,A3.

4)what is the output of the follwing code?

ronnie 4 years ago

please help me solve this question...

using arrays write a simple program to display numbers 1-20.

suraweera 4 years ago

please, help me to write C program to display index number & name of 5 students by using array based list.

ricardo 4 years ago

hi...i had to put it this way to get the results:

main (void)


remove the clrscr();

to get it worked in Dev c++... was of great help :D


saiba 4 years ago


write one more programme for multi dimentional array..

rajkishor09 profile image

rajkishor09 4 years ago from Bangalore, Karnataka, INDIA Author

mikzz 4 years ago

int array [9][9];

assigning values from 1 to 9

magic square..

deepanshu 3 years ago

good information 3 years ago

hi! hello! mam ,sir, ahm i need some example in arrays in how to run a programm..

manisha 3 years ago

i want user se 10 no. enter kraye then user hi unme se koi no. search kare ki wo no. jo user ne enter kiye unme h ya nhi agar h toh print ho "element found" agar nhi toh print ho "element no found"

cokemaster 2 years ago

great hub...

improzee 2 years ago

please give me a sample of this program.

A software company has requested you to implement a Computer Information System that will keep up to a maximum of 50 Computer data. The computer’s information to be kept is:

• ComputerID – int

• ComputerName – 50 characters

• ProcessorSpeed – integer

• RAM - Integer

• OperatingSystem – 50 characters

• Price - float

You would need to create a Computer structure and an array called Computers. You are requested to test the Computer Information System developed by performing the tasks b) to e), and display its output.

a) Declare the Computer structure and the Computers array, using the information given above.

b) Insert 5 new computers using a sequential ComputerID

c) Search for a particular computer by ComputerID

d) Search for a particular computer by ComputerName

e) Display a list of all computers

umeed 2 years ago

Plzzz help me!

How to write a progam that shows 3 no. of rows ,two having lists of integers with size [9] and the third shows their sum by the help of array?????????

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